MIT News - Space, astronomy and planetary science - NASA - Kavli Institute - Exoplanets - space - Astronomy MIT News is dedicated to communicating to the media and the public the news and achievements of the students, faculty, staff and the greater MIT community. en Wed, 16 Oct 2019 00:00:00 -0400 Assembler robots make large structures from little pieces Systems of tiny robots may someday build high-performance structures, from airplanes to space settlements. Wed, 16 Oct 2019 00:00:00 -0400 David L. Chandler | MIT News Office <p>Today’s commercial aircraft are typically manufactured in sections, often in different locations — wings at one factory, fuselage sections at another, tail components somewhere else — and then flown to a central plant in huge cargo planes for final assembly.</p> <p>But what if the final assembly was the only assembly, with the whole plane built out of a large array of tiny identical pieces, all put together by an army of tiny robots?</p> <p>That’s the vision that graduate student Benjamin Jenett, working with Professor Neil Gershenfeld in MIT’s Center for Bits and Atoms (CBA), has been pursuing as his doctoral thesis work. It’s now reached the point that prototype versions of such robots can assemble small structures and even work together as a team to build up a larger assemblies.</p> <p>The new work appears in the October issue of the <em>IEEE Robotics and Automation Letters</em>, in a paper by Jenett, Gershenfeld, fellow graduate student Amira Abdel-Rahman, and CBA alumnus Kenneth Cheung SM ’07, PhD ’12, who is now at NASA’s Ames Research Center, where he leads the <a href="" target="_blank">ARMADAS</a> project to design a lunar base that could be built with robotic assembly.</p> <p>“This paper is a treat,” says Aaron Becker, an associate professor of electrical and computer engineering at the University of Houston, who was not associated with this work. “It combines top-notch mechanical design with jaw-dropping demonstrations, new robotic hardware, and a simulation suite with over 100,000 elements,” he says.</p> <p>“What’s at the heart of this is a new kind of robotics, that we call relative robots,” Gershenfeld says. Historically, he explains, there have been two broad categories of robotics — ones made out of expensive custom components that are carefully optimized for particular applications such as factory assembly, and ones made from inexpensive mass-produced modules with much lower performance. The new robots, however, are an alternative to both. They’re much simpler than the former, while much more capable than the latter, and they have the potential to revolutionize the production of large-scale systems, from airplanes to bridges to entire buildings.</p> <p><img alt="" src="/sites/" style="width: 500px; height: 281px;" /></p> <p><em><span style="font-size: 10px;"><span style="caret-color: rgb(0, 0, 0); color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; text-size-adjust: auto;">Experiments demonstrating&nbsp;relative robotic assembly of 1D, 2D, and 3D discrete&nbsp;cellular structures</span></span></em></p> <p>According to Gershenfeld, the key difference lies in the relationship between the robotic device and the materials that it is handling and manipulating. With these new kinds of robots, “you can’t separate the robot from the structure — they work together as a system,” he says. For example, while most mobile robots require highly precise navigation systems to keep track of their position, the new assembler robots only need to keep track of where they are in relation to the small subunits, called voxels, that they are currently working on. Every time the robot takes a step onto the next voxel, it readjusts its sense of position, always in relation to the specific components that it is standing on at the moment.</p> <p>The underlying vision is that just as the most complex of images can be reproduced by using an array of pixels on a screen, virtually any physical object can be recreated as an array of smaller three-dimensional pieces, or voxels, which can themselves be made up of simple struts and nodes. The team has shown that these simple components can be arranged to distribute loads efficiently; they are largely made up of open space so that the overall weight of the structure is minimized. The units can be picked up and placed in position next to one another by the simple assemblers, and then fastened together using latching systems built into each voxel.</p> <p>The robots themselves resemble a small arm, with two long segments that are hinged in the middle, and devices for clamping onto the voxel structures on each end. The simple devices move around like inchworms, advancing along a row of voxels by repeatedly opening and closing their V-shaped bodies to move from one to the next. Jenett has dubbed the little robots BILL-E (a nod to the movie robot WALL-E), which stands for Bipedal Isotropic Lattice Locomoting Explorer.</p> <p>Jenett has built several versions of the assemblers as proof-of-concept designs, along with corresponding voxel designs featuring latching mechanisms to easily attach or detach each one from its neighbors. He has used these prototypes to demonstrate the assembly of the blocks into linear, two-dimensional, and three-dimensional structures. “We’re not putting the precision in the robot; the precision comes from the structure” as it gradually takes shape, Jenett says. “That’s different from all other robots. It just needs to know where its next step is.”</p> <p>As it works on assembling the pieces, each of the tiny robots can count its steps over the structure, says Gershenfeld, who is the director of CBA. Along with navigation, this lets the robots correct errors at each step, eliminating most of the complexity of typical robotic systems, he says. “It’s missing most of the usual control systems, but as long as it doesn’t miss a step, it knows where it is.” For practical assembly applications, swarms of such units could be working together to speed up the process, thanks to control software developed by Abdel-Rahman that can allow the robots to coordinate their work and avoid getting in each other’s way.</p> <p>This kind of assembly of large structures from identical subunits using a simple robotic system, much like a child assembling a large castle out of LEGO blocks, has already attracted the interest of some major potential users, including NASA, MIT’s collaborator on this research, and the European aerospace company Airbus SE, which also helped to sponsor the study.</p> <p><img alt="" src="/sites/" /></p> <p><em><span style="font-size: 10px;">Computer simulation shows a group of four assembler robots at work on building a three-dimensional structure. Whole swarms of such robots could be unleashed to create large structures such as airplane wings or space habitats. Illustration courtesy of the researchers</span></em></p> <p>One advantage of such assembly is that repairs and maintenance can be handled easily by the same kind of robotic process as the initial assembly. Damaged sections can be disassembled from the structure and replaced with new ones, producing a structure that is just as robust as the original. “Unbuilding is as important as building,” Gershenfeld says, and this process can also be used to make modifications or improvements to the system over time.</p> <p>“For a space station or a lunar habitat, these robots would live on the structure, continuously maintaining and repairing it,” says Jenett.</p> <p>Ultimately, such systems could be used to construct entire buildings, especially in difficult environments such as in space, or on the moon or Mars, Gershenfeld says. This could eliminate the need to ship large preassembled structures all the way from Earth. Instead it could be possible to send large batches of the tiny subunits — or form them from local materials using systems that could crank out these subunits at their final destination point. “If you can make a jumbo jet, you can make a building,” Gershenfeld says.</p> <p>Sandor Fekete, director of the Institute of Operating Systems and Computer Networks at the Technical University of Braunschweig, in Germany, who was not involved in this work, says “Ultralight, digital materials such as [these] open amazing perspectives for constructing efficient, complex, large-scale structures, which are of vital importance in aerospace applications.”</p> <p>But assembling such systems is a challenge, says Fekete, who plans to join the research team for further development of the control systems. “This is where the use of small and simple robots promises to provide the next breakthrough: Robots don’t get tired or bored, and using many miniature robots seems like the only way to get this critical job done. This extremely original and clever work by Ben Jenett and collaborators makes a giant leap towards the construction of dynamically adjustable airplane wings, enormous solar sails or even reconfigurable space habitats.”</p> <p>In the process, Gershenfeld says, “we feel like we’re uncovering a new field of hybrid material-robot systems.”</p> Photo shows two prototype assembler robots at work putting together a series of small units, known as voxels, into a larger structure.Image courtesy of Benjamin JenettResearch, School of Architecture and Planning, Center for Bits and Atoms, Robots, Self-assembly, 3-D printing, Robotics, NASA Astronomers use giant galaxy cluster as X-ray magnifying lens New lens technique spots tiny dwarf galaxy in the first, super-energetic stages of star formation. Mon, 14 Oct 2019 10:59:59 -0400 Jennifer Chu | MIT News Office <p>Astronomers at MIT and elsewhere have used a massive cluster of galaxies as an X-ray magnifying glass to peer back in time, to nearly 9.4 billion years ago. In the process, they spotted a tiny dwarf galaxy in its very first, high-energy stages of star formation.</p> <p>While galaxy clusters have been used to magnify objects at optical wavelengths, this is the first time scientists have leveraged these massive gravitational giants to zoom in on extreme, distant, X-ray-emitting phenomena.</p> <p>What they detected appears to be a blue speck of an infant galaxy, about 1/10,000 the size of our Milky Way, in the midst of churning out its first stars — supermassive, cosmically short-lived objects that emit high-energy X-rays, which the researchers detected in the form of a bright blue arc.</p> <p>“It’s this little blue smudge, meaning it’s a very small galaxy that contains a lot of super-hot, very massive young stars that formed recently,” says Matthew Bayliss, a research scientist in MIT’s Kavli Institute for Astrophysics and Space Research. “This galaxy is similar to the very first galaxies that formed in the universe … the kind of which no one has ever seen in X-ray in the distant universe before.”</p> <p>Bayliss says the detection of this single, distant galaxy is proof that scientists can use galaxy clusters as natural X-ray magnifiers, to pick out extreme, highly energetic phenomena in the universe’s early history.</p> <p>“With this technique, we could, in the future, zoom in on a distant galaxy and age-date different parts of it — to say, this part has stars that formed 200 million years ago, versus another part that formed 50 million years ago, and pick them apart in a way you cannot otherwise do,” says Bayliss, who will be moving on to the University of Cincinnati as an assistant professor of physics.</p> <p>He and his co-authors, including Michael McDonald, assistant professor of physics at MIT, have published their results today in the journal <em>Nature Astronomy</em><em>. </em></p> <p><strong>A candle in the light</strong></p> <p>Galaxy clusters are the most massive objects in the universe, composed of thousands of galaxies, all bound together by gravity as one enormous, powerful force. Galaxy clusters are so massive, and their gravitational pull is so strong, that they can distort the fabric of space-time, bending the universe and any surrounding light, much like an elephant would stretch and warp a trapeze net.</p> <p>Scientists have used galaxy clusters as cosmic magnifying glasses, with a technique known as gravitational lensing. The idea is that if scientists can approximate the mass of a galaxy cluster, they can estimate its gravitational effects on any surrounding light, as well as the angle at which a cluster may deflect that light.</p> <p>For instance, imagine if an observer, facing a galaxy cluster, were trying to detect an object, such as a single galaxy, behind that cluster. The light emitted by that object would travel straight toward the cluster, then bend around the cluster. It would continue traveling toward the observer, though at slightly different angles, appearing to the observer as mirrored images of the same object, which in the end can be combined as a single, “magnified” image.</p> <p>Scientists have used galaxy clusters to magnify objects at optical wavelengths, but never in the X-ray band of the electromagnetic spectrum, mainly because galaxy clusters themselves emit an enormous amount of X-rays. Scientists have thought that any X-rays coming from a background source would be impossible to discern from the cluster’s own glare.</p> <p>“If you’re trying to see an X-ray source behind a cluster, it’s like trying to see a candle next to a really bright light,” Bayliss says. “So we knew this was a challenging measurement to make.”</p> <p><strong>X-ray subtraction</strong></p> <p>The researchers wondered: Could they subtract that bright light and see the candle behind it? In other words, could they remove the X-ray emissions coming from the galaxy cluster, to view the much fainter X-rays coming from an object, behind and magnified by the cluster?</p> <p>The team tested this idea with observations taken by NASA’s Chandra X-ray Observatory, one of the world’s most powerful X-ray space telescopes. They looked in particular at Chandra’s measurements of the Phoenix cluster, a distant galaxy cluster located 5.7 billion light-years from Earth, which has been estimated to be about a quadrillion times as massive as the sun, with gravitational effects that should make it a powerful, natural magnifying lens.</p> <p>“The idea is to take whatever your best X-ray telescope is — in this case, Chandra — and use a natural lens to magnify and effectively make Chandra bigger, so you can see more distant things,” Bayliss says.</p> <p>He and his colleagues analyzed observations of the Phoenix cluster, taken continuously by Chandra for over a month. They also looked at images of the cluster taken by two optical and infrared telescopes — the Hubble Space Telescope and the Magellan telescope in Chile. With all these various views, the team developed a model to characterize the cluster’s optical effects, which allowed the researchers to precisely measure the X-ray emissions from the cluster itself, and subtract it from the data.</p> <p>They were left with two similar patterns of X-ray emissions around the cluster, which they determined were “lensed,” or gravitationally bent, by the cluster. When they traced the emissions backward in time, they found that they all originated from a single, distant source: a tiny dwarf galaxy from 9.4 billion years ago, when the universe itself was roughly 4.4 billion years old — about a third of its current age.</p> <p>“Previously, Chandra had seen only a handful of things at this distance,” Bayliss says. “In less than 10 percent of the time, we discovered this object, similarly far away. And gravitational lensing is what let us do it.”</p> <p>The combination of Chandra and the Phoenix cluster’s natural lensing power enabled the team to see the tiny galaxy hiding behind the cluster, magnified about 60 times. At this resolution, they were able to zoom in to discern two distinct clumps within the galaxy, one producing many more X-rays than the other.</p> <p>As X-rays are typically produced during extreme, short-lived phenomena, the researchers believe that the first X-ray-rich clump signals a part of the dwarf galaxy that has very recently formed supermassive stars, while the quieter region is an older region that contains more mature stars.</p> <p>“We’re catching this galaxy at a very useful stage, where it’s got these really young stars,” Bayliss says. “Every galaxy had to start out in this phase, but we don’t see a lot of these kinds of galaxies in our own neighborhood. Now we can go back in time, look in the distant universe, find galaxies in this early phase of their life, and start to study how star formation is different there.”</p> <p>This research was funded, in part, by NASA, and by the Space Telescope Science Institute.</p> Researchers have for the first time used a massive cluster of galaxies as a huge magnifying lens to detect a small, star-forming dwarf galaxy.Image: Felice Frankel and Christine Daniloff, MITAstronomy, Astrophysics, Kavli Institute, NASA, Research, Satellites, School of Science, Space, astronomy and planetary science, Stars, Physics Scientists observe a single quantum vibration under ordinary conditions Studying a common material at room temperature, researchers bring quantum behavior “closer to our daily life.” Sun, 06 Oct 2019 23:59:59 -0400 Jennifer Chu | MIT News Office <p>When a guitar string is plucked, it vibrates as any vibrating object would, rising and falling like a wave, as the laws of classical physics predict. But under the laws of quantum mechanics, which describe the way physics works at the atomic scale, vibrations should behave not only as waves, but also as particles. The same guitar string, when observed at a quantum level, should vibrate as individual units of energy known as phonons.</p> <p>Now scientists at MIT and the Swiss Federal Institute of Technology have for the first time created and observed a single phonon in a common material at room temperature.</p> <p>Until now, single phonons have only been observed at ultracold temperatures and in precisely engineered, microscopic materials that researchers must probe in a vacuum. In contrast, the team has created and observed single phonons in a piece of diamond sitting in open air at room temperature. The results, the researchers write in a paper published today in <em>Physical Review X</em>, “bring quantum behavior closer to our daily life.”</p> <p>“There is a dichotomy between our daily experience of what a vibration is — a wave — and what quantum mechanics tells us it must be — a particle,” says Vivishek Sudhir, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “Our experiment, because it is conducted at very tangible conditions, breaks this tension between our daily experience and what physics tells us must be the case.”</p> <p>The technique the team developed can now be used to probe other common materials for quantum vibrations. This may help researchers characterize the atomic processes in solar cells, as well as identify why certain materials are superconducting at high temperatures. From an engineering perspective, the team’s technique can be used to identify common phonon-carrying materials that may make ideal interconnects, or transmission lines, between the quantum computers of the future.</p> <p>“What our work means is that we now have access to a much wider palette of systems to choose from,” says Sudhir, one of the paper’s lead authors.</p> <p>Sudhir’s co-authors are Santiago Tarrago Velez, Kilian Seibold, Nils Kipfer, Mitchell Anderson, and Christophe Galland, of the Swiss Federal Institute of Technology.</p> <p><strong>“Democratizing quantum mechanics”</strong></p> <p>Phonons, the individual particles of vibration described by quantum mechanics, are also associated with heat. For instance, when a crystal, made from orderly lattices of interconnected atoms, is heated at one end, quantum mechanics predicts that heat travels through the crystal in the form of phonons, or individual vibrations of the bonds between molecules.</p> <p>Single phonons have been extremely difficult to detect, mainly because of their sensitivity to heat. Phonons are susceptible to any thermal energy that is greater than their own. If phonons are inherently low in energy, then exposure to higher thermal energies could trigger a material’s phonons to excite en masse, making detection of a single photon a needle-in-a-haystack endeavor.</p> <p>The first efforts to observe single phonons did so with materials specially engineered to harbor very few phonons, at relatively high energies. These researchers then submerged the materials in near-absolute-zero refrigerators Sudhir describes as “brutally, aggressively cold,” to ensure that the surrounding thermal energy was lower than the energy of the phonons in the material.</p> <p>“If that’s the case, then the [phonon] vibration cannot borrow energy from the thermal environment to excite more than one phonon,” Sudhir explains.</p> <p>The researchers then shot a pulse of photons (particles of light) into the material, hoping that one photon would interact with a single phonon. When that happens, the photon, in a process known as Raman scattering, should reflect back out at a different energy imparted to it by the interacting phonon. In this way, researchers were able to detect single phonons, though at ultracold temperatures, and in carefully engineered materials.</p> <p>“What we’ve done here is to ask the question, how do you get rid of this complicated environment you’ve created around this object, and bring this quantum effect to our setting, to see it in more common materials,” Sudhir says. “It’s like democratizing quantum mechanics in some sense.”</p> <p><strong>One in a million</strong></p> <p>For the new study, the team looked to diamond as a test subject. In diamond, phonons naturally operate at high frequencies, of tens of terahertz — so high that, at room temperature, the energy of a single phonon is higher than the surrounding thermal energy.</p> <p>“When this crystal of diamond sits at room temperature, phonon motion does not even exist, because there’s no energy at room temperature to excite anything,” Sudhir says.</p> <p>Within this vibrationally quiet mix of phonons, the researchers aimed to excite just a single phonon. They sent high-frequency laser pulses, consisting of 100 million photons each, into the diamond —&nbsp;a crystal made up of carbon atoms — on the off chance that one of them would interact and reflect off a phonon. The team would then measure the decreased frequency of the photon involved in the collision — confirmation that it had indeed hit upon a phonon, though this operation wouldn’t be able to discern whether one or more phonons were excited in the process.</p> <p>To decipher the number of phonons excited, the researchers sent a second laser pulse into the diamond, as the phonon’s energy gradually decayed. For each phonon excited by the first pulse, this second pulse can de-excite it, taking away that energy in the form of a new, higher-energy photon. If only one phonon was initially excited, then one new, higher-frequency photon should be created.</p> <p>To confirm this, the researchers placed a semitransparent glass through which this new, higher-frequency photon would exit the diamond, along with two detectors on either side of the glass. Photons do not split, so if multiple phonons were excited then de-excited, the resulting photons should pass through the glass and scatter randomly into both detectors. If just one detector “clicks,” indicating the detection of a single photon, the team can be sure that that photon interacted with a single phonon.</p> <p>“It’s a clever trick we play to make sure we are observing just one phonon,” Sudhir says.</p> <p>The probability of a photon interacting with a phonon is about one in 10 billion. In their experiments, the researchers blasted the diamond with 80 million pulses per second — what Sudhir describes as a “train of millions of billions of photons” over several hours, in order to detect about 1 million photon-phonon interactions. In the end, they found, with statistical significance, that they were able to create and detect a single quantum of vibration.</p> <p>“This is sort of an ambitious claim, and we have to be careful the science is rigorously done, with no room for reasonable doubt,” Sudhir says.</p> <p>When sending in their second laser pulse to verify that single phonons were indeed being created, the researchers delayed this pulse, sending in into the diamond as the excited phonon was beginning to ebb in energy. In this way, they were able to glean the manner in which the phonon itself decayed.</p> <p>“So, not only are we able to probe the birth of a single phonon, but also we’re able to probe its death,” Sudhir says. “Now we can say, ‘go use this technique to study how long it takes for a single phonon to die out in your material of choice.’ That number is very useful. If the time it takes to die is very long, then that material can support coherent phonons. If that’s the case, you can do interesting things with it, like thermal transport in solar cells, and interconnects between quantum computers.”</p> MIT researchers detect a single quantum vibration within a diamond sample (shown here) at room temperature.Image: Sabine GallandEnergy, Physics, Kavli Institute, Mechanical engineering, Materials Science and Engineering, Quantum computing, Research, School of Engineering This is how a “fuzzy” universe may have looked Scientists simulate early galaxy formation in a universe of dark matter that is ultralight, or “fuzzy,” rather than cold or warm. Thu, 03 Oct 2019 10:53:32 -0400 Jennifer Chu | MIT News Office <p>Dark matter was likely the starting ingredient for brewing up the very first galaxies in the universe. Shortly after the Big Bang, particles of dark matter would have clumped together in gravitational “halos,” pulling surrounding gas into their cores, which over time cooled and condensed into the first galaxies.</p> <p>Although dark matter is considered the backbone to the structure of the universe, scientists know very little about its nature, as the particles have so far evaded detection.</p> <p>Now scientists at MIT, Princeton University, and Cambridge University have found that the early universe, and the very first galaxies, would have looked very different depending on the nature of dark matter. For the first time, the team has simulated what early galaxy formation would have looked like if dark matter were “fuzzy,” rather than cold or warm.</p> <p>In the most widely accepted scenario, dark matter is cold, made up of slow-moving particles that, aside from gravitational effects, have no interaction with ordinary matter. Warm dark matter is thought to be a slightly lighter and faster version of cold dark matter. And fuzzy dark matter, a relatively new concept, is something entirely different, consisting of ultralight particles, each about 1 octillionth (10<sup>-27</sup>) the mass of an electron (a cold dark matter particle is far heavier — about 10<sup>5</sup> times more massive than an electron).</p> <p>In their simulations, the researchers found that if dark matter is cold, then galaxies in the early universe would have formed in nearly spherical halos. But if the nature of dark matter is fuzzy or warm, the early universe would have looked very different, with galaxies forming first in extended, tail-like filaments. In a fuzzy universe, these filaments would have appeared striated, like star-lit strings on a harp. &nbsp;</p> <p>As new telescopes come online, with the ability to see further back into the early universe, scientists may be able to deduce, from the pattern of galaxy formation, whether the nature of dark matter, which today makes up nearly 85 percent of the matter in the universe, is fuzzy as opposed to cold or warm.</p> <p>“The first galaxies in the early universe may illuminate what type of dark matter we have today,” says Mark Vogelsberger, associate professor of physics in MIT’s Kavli Institute for Astrophysics and Space Research. “Either we see this filament pattern, and fuzzy dark matter is plausible, or we don’t, and we can rule that model out. We now have a blueprint for how to do this.”</p> <p>Vogelsberger is a co-author of a paper appearing today in <em>Physical Review Letters,</em> along with the paper’s lead author, Philip Mocz of Princeton University, and Anastasia Fialkov of Cambridge University and previously the University of Sussex.</p> <p><strong>Fuzzy waves</strong></p> <p>While dark matter has yet to be directly detected, the hypothesis that describes dark matter as cold has proven successful at describing the large-scale structure of the observable universe. As a result, models of galaxy formation are based on the assumption that dark matter is cold.</p> <p>“The problem is, there are some discrepancies between observations and predictions of cold dark matter,” Vogelsberger points out. “For example, if you look at very small galaxies, the inferred distribution of dark matter within these galaxies doesn’t perfectly agree with what theoretical models predict. So there is tension there.”</p> <p>Enter, then, alternative theories for dark matter, including warm, and fuzzy, which researchers have proposed in recent years.</p> <p>“The nature of dark matter is still a mystery,” Fialkov says. “Fuzzy dark matter is motivated by fundamental physics, for instance, string theory, and thus is an interesting dark matter candidate. Cosmic structures hold the key to validating or ruling out such dark matter modles.”</p> <p>Fuzzy dark matter is made up of particles that are so light that they act in a quantum, wave-like fashion, rather than as individual particles. This quantum, fuzzy nature, Mocz says, could have produced early galaxies that look entirely different from what standard models predict for cold dark matter.</p> <p>“Even though in the late universe these different dark matter scenarios may predict similar shapes for galaxies, the first galaxies would be strikingly different, which will give us a clue about what dark matter is,” Mocz says.</p> <p>To see how different a cold and a fuzzy early universe could be, the researchers simulated a small, cubic space of the early universe, measuring about 3 million light years across, and ran it forward in time to see how galaxies would form given one of the three dark matter scenarios: cold, warm, and fuzzy.</p> <p>The team began each simulation by assuming a certain distribution of dark matter, which scientists have some idea of, based on measurements of the cosmic microwave background — “relic radiation” that was emitted by, and was detected just 400,000 years after, the Big Bang.</p> <p>“Dark matter doesn’t have a constant density, even at these early times,” Vogelsberger says. “There are tiny perturbations on top of a constant density field.”</p> <p>The researchers were able to use existing algorithms to simulate galaxy formation under scenarios of cold and warm dark matter. But to simulate fuzzy dark matter, with its quantum nature, they needed a new approach.</p> <p><strong>A map of harp strings</strong></p> <p>The researchers modified their simulation of cold dark matter, enabling it to solve two extra equations in order to simulate galaxy formation in a fuzzy dark matter universe. The first, Schrödinger’s equation, describes how a quantum particle acts as a wave, while the second, Poisson’s equation, describes how that wave generates a density field, or distribution of dark matter, and how that distribution leads to gravity — the force that eventually pulls in matter to form galaxies. They then coupled this simulation to a model that describes the behavior of gas in the universe, and the way it condenses into galaxies in response to gravitational effects.</p> <p>In all three scenarios, galaxies formed wherever there were over-densities, or large concentrations of gravitationally collapsed dark matter. The pattern of this dark matter, however, was different, depending on whether it was cold, warm, or fuzzy.&nbsp;</p> <p>In a scenario of cold dark matter, galaxies formed in spherical halos, as well as smaller subhalos. Warm dark matter produced &nbsp;first galaxies in tail-like filaments, and no subhalos. This may be due to warm dark matter’s lighter, faster nature, making particles less likely to stick around in smaller, subhalo clumps.</p> <p>Similar to warm dark matter, fuzzy dark matter formed stars along filaments. But then quantum wave effects took over in shaping the galaxies, which formed more striated filaments, like strings on an invisible harp. Vogelsberger says this striated pattern is due to interference, an effect that occurs when two waves overlap. When this occurs, for instance in waves of light, the points where the crests and troughs of each wave align form darker spots, creating an alternating pattern of bright and dark regions.</p> <p>In the case of fuzzy dark matter, instead of bright and dark points, it generates an alternating pattern of over-dense and under-dense concentrations of dark matter.</p> <p>“You would get a lot of gravitational pull at these over-densities, and the gas would follow, and at some point would form galaxies along those over-densities, and not the under-densities,” Vogelsberger explains. “This picture would be replicated throughout the early universe.”</p> <p>The team is developing more detailed predictions of what early galaxies may have looked like in a universe dominated by fuzzy dark matter. Their goal is to provide a map for upcoming telescopes, such as the James Webb Space Telescope, that may be able to look far enough back in time to spot the earliest galaxies. If they see filamentary galaxies such as those simulated by Mocz, Fialkov, Vogelsberger, and their colleagues, it could be the first signs that dark matter’s nature is fuzzy.</p> <p>“It’s this observational test we can provide for the nature of dark matter, based on observations of the early universe, which will become feasible in the next couple of years,” Vogelsberger says.</p> <p>This research was supported, in part, by NASA.</p> A simulation of early galaxy formation under three dark matter scenarios. In a universe filled with cold dark matter, early galaxies would first form in bright halos (far left). If dark matter is instead warm, galaxies would form first in long, tail-like filaments (center). Fuzzy dark matter would produce similar filaments, though striated (far right), like the strings of a harp.Image courtesy of the researchersDark matter, Algorithms, Astronomy, Astrophysics, Kavli Institute, Research, School of Science, space, Space, astronomy and planetary science, Physics Computing and the search for new planets MIT planetary scientists partner with computer scientists to find exoplanets. Mon, 23 Sep 2019 09:00:00 -0400 Brittany Flaherty | School of Science <p>When MIT launched the <a href="">MIT Stephen A. Schwarzman College of Computing</a> this fall, one of the goals was to drive further innovation in computing across all of MIT’s schools. Researchers are already expanding beyond traditional applications of computer science and using these techniques to advance a range of scientific fields, from cancer medicine to anthropology to design — and to the discovery of new planets.</p> <p>Computation has already proven useful for the Transiting Exoplanet Survey Satellite (TESS), a NASA-funded mission led by MIT. Launched from Cape Canaveral in April 2018, TESS is a satellite that takes images of the sky as it orbits the Earth. These images can help researchers find planets orbiting stars beyond our sun, called exoplanets. This work, which is now halfway complete, will reveal more about the other planets within what NASA calls our “solar neighborhood.”&nbsp;</p> <p>“TESS just completed the first of its two-year prime mission, surveying the southern night sky,” says Sara Seager, an astrophysicist and planetary scientist at MIT and deputy director of science for TESS. “TESS found over 1,000 planet candidates and about 20 confirmed planets, some in multiple-planet systems.”</p> <p>While TESS has enabled some impressive discoveries so far, finding these exoplanets is no simple task. TESS is collecting images of more than 200,000 distant stars, saving an image of these planets every two minutes, as well as saving an image of a large swath of sky every 30 minutes. Seager says every two weeks, which is how long it takes the satellite to orbit the Earth, TESS sends about 350 gigabytes of data (once uncompressed) to Earth. While Seager says this is not as much data as people might expect (a 2019 Macbook Pro has up to 512 gigabytes of storage), analyzing the data involves taking many complex factors into consideration.</p> <p>Seager, who says she has long been interested in how computation can be used as a tool for science, began discussing the project with Victor Pankratius, a former principal research scientist in MIT’s Kavli Institute for Astrophysics and Space Research, who is now the director and head of global software engineering at Bosch Sensortec. A trained computer scientist, Pankratius says that after arriving at MIT in 2013, he started thinking about scientific fields that produce big data, but that have not yet fully benefited from computing techniques. After speaking with astronomers like Seager, he learned more about the data their instruments collect and became interested in applying computer-aided discovery techniques to the search for exoplanets.</p> <p>“The universe is a big place,” Pankratius says. “So I think leveraging what we have on the computer science side is a great thing.”&nbsp;</p> <p>The basic idea underlying TESS’ mission is that like our own solar system, in which the Earth and other planets revolve around a central star (the sun), there are other planets beyond our solar system revolving around different stars. The images TESS collects produce light curves — data that show how the brightness of the star changes over time. Researchers are analyzing these light curves to find drops in brightness, which could indicate that a planet is passing in front of the star and temporarily blocking some of its light.&nbsp;</p> <p>“Every time a planet orbits, you would see this brightness go down,” Pankratius says. “It's almost like a heartbeat.”&nbsp;</p> <p>The trouble is that not every dip in brightness is necessarily caused by a passing planet. Seager says machine learning currently comes into play during the “triage” phase of their TESS data analysis, helping them distinguish between potential planets and other things that could cause dips in brightness, like variable stars, which naturally vary in their brightness, or instrument noise.</p> <p>Analysis on planets that pass through triage is still done by scientists who have learned how to “read” light curves. But the team is now using thousands of light curves that have been classified by eye to teach neural networks how to identify exoplanet transits. Computation is helping them narrow down which light curves they should examine in more detail. Liang Yu PhD ’19, a recent physics graduate, built upon an existing code to write the machine learning tool that the team is now using.</p> <p>While helpful for homing in on the most relevant data, Seager says machine learning cannot yet be used to simply find exoplanets. “We still have a lot of work to do,” she says.</p> <p>Pankratius agrees. “What we want to do is basically create computer-aided discovery systems that do this for all [stars] all the time,” he says. “You want to just press a button and say, show me everything. But right now it's still people with some automation vetting all of these light curves.”</p> <p>Seager and Pankratius also co-taught a course that focused on various aspects of computation and artificial intelligence (AI) development in planetary science. Seager says inspiration for the course arose from a growing interest from students to learn about AI and its applications to cutting-edge data science.</p> <p>In 2018, the course allowed students to use actual data collected by TESS to explore machine learning applications for this data. Modeled after another course Seager and Pankratius taught, students in the course were able to choose a scientific problem and learn the computation skills to solve that problem. In this case, students learned about AI techniques and applications to TESS. Seager says students had a great response to the unique class.&nbsp;</p> <p>“As a student, you could actually make a discovery,” Pankratius says. “You can build a machine learning algorithm, run it on this data, and who knows, maybe you will find something new.”</p> <p>Much of the data TESS collects is also readily available as part of a larger citizen science project. Pankratius says anyone with the right tools could start making discoveries of their own. Thanks to cloud connectivity, this is even possible on a cell phone.&nbsp;</p> <p>“If you get bored on your bus ride home, why not search for planets?” he says.</p> <p>Pankratius says this type of collaborative work allows experts in each domain to share their knowledge and learn from each other, rather than each trying to get caught up in the other’s field.&nbsp;&nbsp;</p> <p>“Over time, science has become more specialized, so we need ways to integrate the specialists better,” Pankratius says. The college of computing could help forge more such collaborations, he adds. Pankratius also says it could attract researchers who work at the intersection of these disciplines, who can bridge gaps in understanding between experts.</p> <p>This type of work integrating computer science is already becoming increasingly common across scientific fields, Seager notes. “Machine learning is ‘in vogue’ right now,” she says.&nbsp;</p> <p>Pankratius says that is in part because there is more evidence that leveraging computer science techniques is an effective way to address various types of problems and growing data sets.</p> <p>“We now have demonstrations in different areas that the computer-aided discovery approach doesn’t just work,” Pankratius says. “It actually leads to new discoveries.”</p> Worlds orbiting stars other than our sun are “exoplanets,” and they come in many sizes, from gas giants larger than Jupiter to small, rocky planets. This illustration of a "super-Earth" represents the type of planet that the TESS mission aims to find outside our solar system.Image: M. Kornmesser/ESOMIT Schwarzman College of Computing, Kavli Institute, Astronomy, Astrophysics, EAPS, Exoplanets, NASA, Planetary science, Research, Satellites, School of Engineering, School of Science, Space, astronomy and planetary science, TESS, Artificial intelligence, Physics, Aeronautical and astronautical engineering, Computer science and technology Four from MIT named American Physical Society Fellows for 2019 Matthew Evans, Joseph Formaggio, Markus Klute, and Anne White are named MIT’s newest APS fellows for their contributions to physics. Fri, 20 Sep 2019 14:00:01 -0400 Fernanda Ferreira | School of Science <p>Four members of the MIT community have been elected fellows of the <a href="">American Physical Society</a> (APS) for 2019. The APS fellowship was created in 1921 for those in the physics community to recognize peers who have contributed to advances in physics through original research, innovative applications, teaching, and leadership.</p> <p><a href="">Matthew Evans</a> is a professor of physics, a member of the MIT Kavli Institute of Astrophysics and Space Research, and a member of the MIT Laser Interferometer Gravitational-Wave Observatory (LIGO) research group. Evans was nominated by APS’ Division of Gravitational Physics for his “critical contributions to the development of advanced gravitational-wave detectors, as well as for developing techniques to enable further improvements in detector sensitivity, and for leading community efforts to design future large-scale ground-based detectors.”</p> <p><a href="">Joseph A. Formaggio</a> is a professor of physics and a member of the Laboratory of Nuclear Science. Formaggio was nominated by APS’ Division of Nuclear Physics for his “leadership in the pursuit of neutrino masses determination, and for developing novel technologies to attack the problem of direct detection.”</p> <p><a href="">Markus Klute</a> is a professor of physics and member of the Laboratory of Nuclear Science. Klute was nominated by APS’ Division of Particles and Fields for his “work establishing the coupling of the Higgs boson to tau leptons, and for establishing the physics case for colliders beyond the Large Hadron Collider, including the High Luminosity LHC.”</p> <p><a href="">Anne White</a> is a professor and head of the Department of Nuclear Science and Engineering. Nominated by the APS’ Division of Plasma Physics, White was cited for her “outstanding contributions and leadership in understanding turbulent electron heat transport in magnetically confined fusion plasmas via diagnostic development, novel experimentation, and validation of nonlinear gyrokinetic codes.”</p> Four MIT faculty have been named 2019 American Physics Society Fellows: (left to right) Matthew Evans, Joseph Formaggio, Markus Klute, and Anne White. Photos courtesy of the researchers (Bryce Vickmark for Anne White)Awards, honors and fellowships, Faculty, Physics, LIGO, Kavli Institute, Laboratory for Nuclear Science, Nuclear science and engineering, School of Science, School of Engineering 3Q: Scientists shave estimate of neutrino’s mass in half Joseph Formaggio explains the discovery that the ghostly particle must be no more than 1 electronvolt, half as massive as previously thought. Mon, 16 Sep 2019 23:59:59 -0400 Jennifer Chu | MIT News Office <p><em>An international team of scientists, including researchers at MIT, has come closer to pinning down the mass of the elusive neutrino. These ghost-like particles permeate the universe and yet are thought to be nearly massless, streaming by the millions through our bodies while leaving barely any physical trace. </em></p> <p><em>The researchers have determined that the mass of the neutrino should be no more than 1 electron volt. Scientists previously estimated the upper limit of the neutrino’s mass to be around 2 electron volts, so this new estimate shaves down the neutrino’s mass range by more than half. </em></p> <p><em>The new estimate was determined based on data taken by KATRIN, the Karlsruhe Tritium Neutrino Experiment, at the Karlsruhe Institute of Technology in Germany, and reported at the 2019 Conference on Astroparticle and Underground Physics last week. The experiment triggers tritium gas to decay, which in turn releases neutrinos, along with electrons. While the neutrinos&nbsp; are quick to dissipate, KATRIN’s sequence of magnets directs tritium’s electrons into the the heart of the experiment — a giant 200-ton spectrometer, where the electrons’ mass and energy can be measured, and from there, researchers can calculate the mass of the corresponding neutrinos.</em></p> <p><em>Joseph Formaggio, professor of physics at MIT, is a leading member of the KATRIN experimental group, and spoke with </em>MIT News<em> about the new estimate and the road ahead in the neutrino search.</em></p> <p><strong>Q:</strong> The neutrino, based on KATRIN’s findings, can’t be more massive than 1 electron volt. Put this context for us: How light is this, and how big a deal is it that the neutrino’s maximum mass could be half of what people previously thought?</p> <p><strong>A:</strong> Well, that’s somewhat of a difficult question, since people (myself included) don’t really have an intuitive sense of what the mass is of&nbsp;any&nbsp;particle, but let’s try. Consider something very small, like a virus. Each virus is made up of roughly 10 million&nbsp;proton<em>s</em>. Each proton weighs about 2,000 times more than each&nbsp;electron&nbsp;inside that virus. And what our results showed is that the neutrino has a mass less than 1/ 500,000 of a single electron!</p> <p>Let me put it another way. In each cubic centimeter of space around you, there are about 300 neutrinos zipping through. These are remnants of the early universe, just after the Big Bang. If you added up all the neutrinos residing inside the sun, you’d get about a kilogram or less. So, yeah, it’s small.</p> <p><strong>Q:</strong> What went into determining this new mass limit for the neutrino, and what was MIT’s role in the search?</p> <p><strong>A:</strong> This new mass limit comes from studying the radioactive decay of tritium, an isotope of hydrogen. When tritium decays, it produces a helium-3 ion, an electron, and an antineutrino. We actually never see the antineutrino, however; the electron carries information about the neutrino’s mass. By studying the energy distribution of the electrons ejected at the highest energies allowed, we can deduce the mass of the neutrino, thanks to Einstein’s equation, E=mc<sup>2</sup>.</p> <p>However, studying those high-energy electrons is very difficult. For one thing, all the information about the neutrino is embedded in a tiny fraction of the spectrum — less than 1 billionth of decays are of use for this measurement. So, we need a lot of tritium inventory. We also need to measure the energy of those electrons very, very precisely. This is why the KATRIN experiment is so tricky to build. Our very first measurement presented today is the culmination of almost two decades of hard work and planning.</p> <p>MIT joined the KATRIN experiment when I came to Boston in 2005. Our group helped develop the simulation tools to understand the response of our detector to high precision. More recently, we have been involved in developing tools to analyze the data collected by the experiment.</p> <p><strong>Q:</strong> Why does the mass of a neutrino matter, and what will it take to zero in on its exact mass?</p> <p><strong>A:</strong> The fact that neutrinos have any mass at all was a surprise to many physicists. Our earlier models predicted that the neutrino should have exactly zero mass, an assumption dispelled by the <a href="">discovery</a> that neutrinos oscillate between different types. That means we do not really understand the mechanism responsible for neutrino masses, and it is likely to be very different than how other particles attain mass. Also, our universe is filled with primordial neutrinos from the Big Bang. Even a tiny mass has a significant impact on the structure and evolution of the universe because they are so aplenty.</p> <p>This measurement represents just the beginning of KATRIN’s measurement. With just about one month of data, we were able to improve previous experimental limits by a factor of two. Over the next few years, these limits will steadily improve, hopefully resulting in a positive signal (rather than just a limit). There are also a number of other direct neutrino mass experiments on the horizon that are also competing to reach greater sensitivity, and with it, discovery!</p> KATRIN’s spectrometer, shown here, precisely measures the energy of electrons emitted in the decay of tritium, which has helped scientists come closer to pinning down the mass of the ghost-like neutrino.Image: The KATRIN CollaborationAstrophysics, Physics, Research, School of Science, 3 Questions, Space, astronomy and planetary science, Neutrinos, Laboratory for Nuclear Science TESS team is awarded NASA&#039;s Silver Achievement Medal The honor recognizes the &quot;stellar achievement&quot; of the people behind the exoplanet-seeking satellite. Thu, 12 Sep 2019 13:25:01 -0400 Kylie Foy | Lincoln Laboratory <p>On Sept. 5, NASA awarded a Silver Achievement Medal to the Transiting Exoplanet Survey Satellite (TESS) team. The award was presented during a ceremony at the NASA Goddard Space Flight Center as part of NASA's 2019 Agency Honor Awards.</p> <p>The Silver Achievement Medal is given by NASA center directors in recognition of government and non-government individuals or teams for "a stellar achievement that supports one or more of NASA's core values, when it is deemed to be extraordinarily important and appropriate to recognize such achievement in a timely and personalized manner."</p> <p>TESS was launched in April 2018 as the next step in NASA's search for exoplanets, which are planets outside of Earth's solar system. The four cameras aboard TESS were conceived, designed, and built by the MIT Kavli Institute for Astrophysics and Space Research and by MIT Lincoln Laboratory. Together, the cameras will gaze at 85 percent of the sky over the course of its mission, looking for discreet dips in light that signify that a planet is passing in front of a star.</p> <p>George Ricker, TESS principal investigator and senior research scientist at the Kavli Institute, says that "the NASA Silver Achievement Medal recognizes the revolutionary impact that TESS is now having on the emerging field of exoplanets, as well as TESS’ revealing of exciting new insights in stellar and extragalactic astrophysics. The members of the TESS science and engineering teams can rightly be proud of the marvelous instrument which they have brought into operation in just five years from our mission’s selection by NASA. I am personally gratified to have been part of this impressive MIT-led team."</p> <p>Lincoln Laboratory group leader Gregory Berthiaume, who served as the instrument manager for the TESS mission, adds that he is proud and honored to be a part of the TESS team, and congratulated the "incredibly talented and dedicated staff who provided key technologies and capabilities that enabled the TESS instrument."</p> <p>"The team is continuing to work hard to find planet candidates in the TESS data, and new planet candidates that may help us answer some of the intriguing questions in exoplanets today," says Sara Seager, the deputy science director of TESS who is also the Class of 1941 Professor Chair in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS) with appointments in the departments of Physics and Aeronautics and Astronautics.</p> <p>Approximately 250 MIT scientists and engineers are included as recipients of the Silver Achievement Medal for their role on the TESS team.&nbsp;</p> <p>Since its launch, TESS has discovered two dozen new planets and 850 more potential worlds that have yet to be confirmed. Scientists expect TESS to discover thousands of new exoplanets by the time its mission is over.</p> <p>TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. George Ricker of MIT’s Kavli Institute, serves as principal investigator for the mission.&nbsp;Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics, and the Space Telescope Science Institute. More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.</p> The Transiting Exoplanet Survey Satellite is inspected before its launch in April 2018. Approximately 250 MIT scientists and engineers are included as recipients of the NASA Silver Achievement Medal for their role in the TESS mission.Photo: Goddard Space Flight CenterLincoln Laboratory, Kavli Institute, Exoplanets, TESS, Astronomy, Astrophysics, Awards, honors and fellowships, Planetary science, Physics, School of Science, EAPS, Space, astronomy and planetary science, Aeronautical and astronautical engineering Scientists detect tones in the ringing of a newborn black hole for the first time Results support Einstein’s theory and the idea that black holes have no “hair.” Thu, 12 Sep 2019 09:29:58 -0400 Jennifer Chu | MIT News Office <p>If Albert Einstein’s theory of general relativity holds true, then a black hole, born from the cosmically quaking collisions of two massive black holes, should itself “ring” in the aftermath, producing gravitational waves much like a struck bell reverbates sound waves. Einstein predicted that the particular pitch and decay of these gravitational waves should be a direct signature of the newly formed black hole’s mass and spin.</p> <p>Now, physicists from MIT and elsewhere have studied the ringing of an infant black hole, and found that the pattern of this ringing does, in fact, predict the black hole’s mass and spin — more evidence that Einstein was right all along.</p> <p>The findings, published today in <em>Physical Review Letters</em>, also favor the idea that black holes lack any sort of “hair” — a metaphor referring to the idea that black holes, according to Einstein’s theory, should exhibit just three observable properties: mass, spin, and electric charge. All other characteristics, which the physicist John Wheeler termed “hair,” should be swallowed up by the black hole itself, and would therefore be unobservable.</p> <p>The team’s findings today support the idea that black holes are, in fact, hairless. The researchers were able to identify the pattern of a black hole’s ringing, and, using Einstein’s equations, calculated the mass and spin that the black hole should have, given its ringing pattern. These calculations matched measurements of the black hole’s mass and spin made previously by others.</p> <p>If the team’s calculations deviated significantly from the measurements, it would have suggested that the black hole’s ringing encodes properties other than mass, spin, and electric charge — tantalizing evidence of physics beyond what Einstein’s theory can explain. But as it turns out, the black hole’s ringing pattern is a direct signature of its mass and spin, giving support to the notion that black holes are bald-faced giants, lacking any extraneous, hair-like properties.</p> <p>“We all expect general relativity to be correct, but this is the first time we have confirmed it in this way,” says the study’s lead author, Maximiliano Isi, a NASA Einstein Fellow in MIT’s Kavli Institute for Astrophysics and Space Research. “This is the first experimental measurement that succeeds in directly testing the no-hair theorem. It doesn’t mean black holes couldn’t have hair. It means the picture of black holes with no hair lives for one more day.”</p> <p><strong>A chirp, decoded</strong></p> <p>On Sept. 14, 2015, scientists made the <a href="">first-ever detection</a> of gravitational waves — infinitesimal ripples in space-time, emanating from distant, violent cosmic phenomena. The detection, named GW150914, was made by LIGO, the Laser Interferometer Gravitational-wave Observatory. Once scientists cleared away the noise and zoomed in on the signal, they observed a waveform that quickly crescendoed before fading away. When they translated the signal into sound, they heard something resembling a “chirp.”</p> <p>Scientists determined that the gravitational waves were set off by the rapid inspiraling of two massive black holes. The peak of the signal — the loudest part of the chirp — linked to the very moment when the black holes collided, merging into a single, new black hole. While this infant black hole gave off gravitational waves of its own, its signature ringing, physicists assumed, would be too faint to decipher amid the clamor of the initial collision.&nbsp;Thus, traces of this ringing were only identified some time after the peak, where the signal was too faint to study in detail.</p> <p>Isi and his colleagues, however, found a way to extract the black hole’s reverberation from the moments immediately after the signal’s peak. In previous work led by Isi’s co-author, Matthew Giesler of Caltech, the team showed through simulations that such a signal, and particularly the portion right after the peak, contains “overtones” — a family of loud, short-lived tones. When they reanalyzed the signal, taking overtones into account, the researchers discovered that they could successfully isolate a ringing pattern that was specific to a newly formed black hole.</p> <p>In the team’s new paper, the researchers applied this technique to actual data from the GW150914 detection, concentrating on the last few milliseconds of the signal, immediately following the chirp’s peak. Taking into account the signal’s overtones, they were able to discern a ringing coming from the new, infant black hole. Specifically, they identified two distinct tones, each with a pitch and decay rate that they were able to measure.</p> <p>“We detect an overall gravitational wave signal that’s made up of multiple frequencies, which fade away at different rates, like the different pitches that make up a sound,” Isi says. “Each frequency or tone corresponds to a vibrational frequency of the new black hole.”</p> <p><strong>Listening beyond Einstein</strong></p> <p>Einstein’s theory of general relativity predicts that the pitch and decay of a black hole’s gravitational waves should be a direct product of its mass and spin. That is, a black hole of a given mass and spin can only produce tones of a certain pitch and decay. As a test of Einstein’s theory, the team used the equations of general relativity to calculate the newly formed black hole’s mass and spin, given the pitch and decay of the two tones they detected.</p> <p>They found their calculations matched with measurements of the black hole’s mass and spin previously made by others. Isi says the results demonstrate that researchers can, in fact, use the very loudest, most detectable parts of a gravitational wave signal to discern a new black hole’s ringing, where before, scientists assumed that this ringing could only be detected within the much fainter end of the gravitational wave signal, and identifying many tones would require much more sensitive instruments than what currently exist.</p> <p>“This is exciting for the community because it shows these kinds of studies are possible now, not in 20 years,” Isi says.</p> <p>As LIGO improves its resolution, and more sensitive instruments come online in the future, researchers will be able to use the group’s methods to “hear” the ringing of other newly born black holes. And if they happen to pick up tones that don’t quite match up with Einstein’s predictions, that could be an even more exciting prospect.</p> <p>“In the future, we’ll have better detectors on Earth and in space, and will be able to see not just two, but tens of modes, and pin down their properties precisely,” Isi says. “If these are not black holes as Einstein predicts, if they are more exotic objects like wormholes or boson stars, they may not ring in the same way, and we’ll have a chance of seeing them.”</p> <p>This research was supported, in part, by NASA, the Sherman Fairchild Foundation, the Simons Foundation, and the National Science Foundation.</p> MIT scientists have captured the “ringing” of a newly-formed black hole, in the form of gravitational waves, depicted in this artist’s illustration.Astronomy, Astrophysics, Black holes, LIGO, Kavli Institute, Physics, Research, School of Science, Space, astronomy and planetary science, NASA, National Science Foundation (NSF) Breakthrough Prize in Fundamental Physics awarded to Event Horizon Telescope Collaboration for black hole observation Nearly 30 MIT-affiliated researchers will share in the prize, while David Jay Julius ’77 wins Breakthrough Prize in Life Sciences; assistant professor of physics Max Metlitski shares New Horizons prize with Xie Chen PhD ’12 and Michael Levin PhD ’06. Fri, 06 Sep 2019 11:58:57 -0400 MIT News Office <p>The Event Horizon Telescope (EHT) Collaboration, including scientists and engineers from MIT, will receive a 2020 Breakthrough Prize in Fundamental Physics. The team is being honored for making the <a href="">first direct detection</a> of a black hole. Assistant professor of physics Max Metlitski and several MIT alumni are also receiving awards from the Breakthrough Prize Foundation.</p> <p>The $3 million fundamental physics prize will be shared equally with the 347 EHT researchers from around the world who co-authored the six papers published on April 10, 2019, which reported the detection of the supermassive black hole at the heart of Messier 87, or M87, a galaxy within the Virgo galaxy cluster.</p> <p>The new laureates will be recognized at an awards ceremony in Mountain View, California, on Nov. 3.</p> <p><strong>Earth-sized telescope</strong></p> <p>The EHT is a global network of radio telescopes that work together as one virtual telescope, with a resolution sharp enough to “see” a black hole’s shadow.</p> <p>Researchers at MIT’s Haystack Observatory made several key contributions as members of the global collaboration, such as developing the ultrafast devices that record the vast volumes of data captured by each telescope.</p> <p>After the observing run ended, the data were sent to Haystack and to the Max Planck Institute for Radio Astronomy, where they were processed using a specialized supercomputer called a correlator, also developed by Haystack researchers. Teams at both institutions then undertook the painstaking process of “correlating” the data and ensuring they were rigorously verified before being released to the independent teams that would create the images of M87.</p> <p>The result, according to the Breakthrough Prize citation, was “an image of this galactic monster, silhouetted against hot gas swirling around the black hole, that matched expectations from Einstein's theory of gravity.”</p> <p>MIT-affliated scientists and engineers who will share in the prize include researchers and alumni from Haystack Observatory, the Department of Electrical Engineering and Computer Science, the Department of Physics, the Department of Earth, Atmospheric and Planetary Sciences, and the MIT Kavli Institute for Astrophysics and Space Research. They are: Kazunori Akiyama, Frederick K. Baganoff, John Barrett, Christopher Beaudoin, Lindy Blackburn, Katherine L. Bouman, Roger Cappallo, Geoffrey B. Crew, Joseph Crowley, Mark Derome, Sheperd S. Doeleman, Chris Eckert, Vincent L. Fish, William T. Freeman, Michael H. Hecht, Colin Lonsdale, Sera Markoff, Lynn D. Matthews, Stephen R. McWhirter, James Moran, Kotaro Moriyama, Michael Nowak, Joseph Neilsen, Daniel C. M. Palumbo, Michael Poirier, Alan Rogers, Chet Ruszczyk, Jason SooHoo, Don Sousa, Michael Titus, Alan R. Whitney, and Shuo Zhang.</p> <p><strong>Additional accolades</strong></p> <p>The Breakthrough Prize Foundation has also honored assistant professor of physics Maxim Metlitski, awarding him a New Horizons prize, which recognizes early-career achievements in physics and mathematics. Metlitski will share the prize with three collaborators, two of whom are MIT alumni: Xie Chen PhD ’12 of Caltech, Michael Levin PhD ’06 of the University of Chicago, and Lukasz Fidkowski of the University of Washington.</p> <p>The team is being honored “for incisive contributions to the understanding of topological states of matter and the relationships between them,” according to the Breakthrough Prize citation.</p> <p>“Max is part of a very talented group of experimentalists and theorists working on new materials with very unusual properties,” says Peter Fisher, professor and head of the Department of Physics. “These materials are teaching us how quantum mechanics plays an unexpected role in how electrons and vibrations can travel in materials that could result in new technologies.”</p> <p>Metlitski earned a BS in physics and mathematics and an MS in physics from the University of British Columbia. After obtaining his PhD in physics from Harvard University in 2011, he held a postdoctoral position at the Kavli Institute for Theoretical Physics at the University of California at Santa Barbara. He joined MIT’s Department of Physics as an assistant professor in January 2017, following a faculty appointment at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.</p> <p>“On behalf of the School of Science, I congratulate Max Metlitski for this impressive early-career achievement in condensed matter theory,” says Michael Sipser, dean of the MIT School of Science and the Donner Professor of Mathematics. “In addition, I applaud our researchers in the Event Horizon Telescope Collaboration, who contributed to our first images of a black hole.&nbsp;We celebrate our scientists’ pursuit of fundamental research to advance human knowledge and all recipients of these prestigious awards.”</p> <p>David Jay Julius ’77, a professor at the University of California at San Franciso, has also won a 2020 Breakthrough Prize in Life Sciences, for discovering molecules, cells and mechanisms underlying pain sensation. And last month, Daniel Z. Freedman, professor emeritus in MIT’s departments of Mathematics and Physics, <a href="">was awarded</a> a Special Breakthrough Prize in Fundamental Physics.</p> The MIT Haystack Observatory houses a specialized supercomputer called a correlator, which crunched data generated by the EHT project.Image: courtesy of MIT Haystack ObservatoryAstronomy, Astrophysics, Black holes, Haystack Observatory, National Science Foundation (NSF), Faculty, Staff, Alumni/ae, Kavli Institute, Electrical Engineering & Computer Science (eecs), School of Engineering, School of Science, EAPS, space, Space, astronomy and planetary science, awards, Awards, honors and fellowships, Physics Taking the next giant leaps Fifty years after the first moon landing with Apollo 11, the Department of Aeronautics and Astronautics looks to the future of space exploration at MIT. Thu, 05 Sep 2019 15:00:01 -0400 Sara Cody | Department of Aeronautics and Astronautics <p>In July, the world celebrated the 50th anniversary of the historic Apollo 11 moon landing. MIT played an enormous role in that accomplishment, helping to usher in a new age of space exploration. Now MIT faculty, staff, and students are working toward the next great advances — ones that could propel humans back to the moon, and to parts still unknown.&nbsp;&nbsp;</p> <p>“I am hard-pressed to think of another event that brought the world together in such a collective way as the Apollo moon landing,” says Daniel Hastings, the Cecil and Ida Green Education Professor and head of the Department of Aeronautics and Astronautics (AeroAstro). “Since the spring, we have been <a href="" target="_self">celebrating</a> the role <a href="" target="_self">MIT played</a> in getting us there and reflecting on how far technology has come in the past five decades.”&nbsp;</p> <p>“Our community continues to build on the incredible legacy of Apollo,” Hastings adds. Some aspects of future of space exploration, he notes, will follow from lessons learned. Others will come from newly developed technologies that were unimaginable in the 1960s. And still others will arise from novel collaborations that will fuel the next phases of research and discovery.&nbsp;</p> <p>“This is a tremendously exciting time to think about the future of space exploration,” Hastings says. “And MIT is leading the way.”</p> <p><strong>Sticking the landing</strong></p> <p>Making a safe landing — anywhere — can be a life-or-death situation. On Earth, thanks to a network of global positioning satellites and a range of ground-based systems, pilots have instantaneous access to real-time data on every aspect of a landing environment. The moon, however, is not home to any of this precision navigation technology, making it rife with potential danger.&nbsp;</p> <p>NASA’s recent decision to return to moon has made this a more pressing challenge — and one that MIT has risen to before. The former MIT Instrumentation Lab (now the independent Draper) developed the guidance systems that enabled Neil Armstrong and Buzz Aldrin to land safely on the moon, and that were used on all Apollo spacecraft. This system relied on inertial navigation, which integrates acceleration and velocity measurements from electronic sensors on the vehicle and a digital computer to determine the spacecraft’s location. It was a remarkable achievement — the first time that humans traveled in a vehicle controlled by a computer.&nbsp;&nbsp;</p> <p>Today, working in MIT’s Aerospace Controls Lab with Jonathan How, the Richard Cockburn Maclaurin Professor of Aeronautics and Astronautics, graduate student Lena Downes — who is also co-advised by Ted Steiner at Draper — is developing a camera-based navigation system that can sense the terrain beneath the landing vehicle and use that information to update the location estimation. “If we want to explore a crater to determine its age or origin,” Downes explains, “we will need to avoid landing on the more highly-sloped rim of the crater. Since lunar landings can have errors as high as several kilometers, we can’t plan to land too closely to the edge.”&nbsp;</p> <p>Downes’s research on crater detection involves processing images using convolutional neural networks and traditional computer vision methods. The images are combined with other data, such as previous measurements and known crater location information, enabling increased precision vehicle location estimation.</p> <p>“When we return to the moon, we want to visit more interesting locations, but the problem is that more interesting can often mean more hazardous,” says Downes. “Terrain-relative navigation will allow us to explore these locations more safely.”</p> <p><strong>“Make it, don’t take it”</strong></p> <p>NASA also has its sights set on Mars — and with that objective comes a very different challenge: What if something breaks? Given that the estimated travel time to Mars is between 150 and 300 days, there is a relatively high chance that something will break or malfunction during flight. (Just ask Jim Lovell or Fred Haise, whose spacecraft needed serious repairs only 55 hours and 54 minutes into the Apollo 13 mission.)</p> <p>Matthew Moraguez, a graduate student in Professor Olivier L. de Weck’s Engineering Systems Lab, wants to empower astronauts to manufacture whatever they need, whenever they need it. (“On the fly,” you could say).</p> <p>“In-space manufacturing (ISM) — where astronauts can carry out the fabrication, assembly, and integration of components — could revolutionize this paradigm,” says Moraguez. “Since components wouldn’t be limited by launch-related design constraints, ISM could reduce the cost and improve the performance of existing space systems while also enabling entirely new capabilities.”</p> <p>Historically, a key challenge facing ISM is correctly pairing the components with manufacturing processes needed to produce them. Moraguez approached this problem by first defining the constraints created by a stressful launch environment, which can limit the size and weight of a payload. He then itemized the challenges that could potentially be alleviated by ISM and developed cost-estimating relationships and performance models to determine the exact break-even point at which ISM surpasses the current approach.&nbsp;</p> <p>Moraguez points to Made in Space, an additive manufacturing facility that is currently in use on the International Space Station. The facility produces tools and other materials as needed, reducing both the cost and the wait time of replenishing supplies from Earth. Moraguez is now developing physics-based manufacturing models that will determine the size, weight, and power required for the next generation of ISM equipment.</p> <p>“We have been able to evaluate the commercial viability of ISM across a wide range of application areas,” says Moraguez. “Armed with this framework, we aim to determine the best components to produce with ISM and their appropriate manufacturing processes. We want to develop the technology to a point where it truly revolutionizes the future of spaceflight. Ultimately, it could allow humans to travel further into deep space for longer durations than ever before,” he says.&nbsp;</p> <p><strong>Partnering with industry</strong></p> <p>The MIT Instrumentation Lab was awarded the first contract for the Apollo program in 1961. In one brief paragraph on a <a href="" target="_blank">Western Union telegram</a>, the lab was charged with developing the program’s guidance and control system. Today the future of space exploration depends as much as ever on deep collaborations.&nbsp;</p> <p>Boeing is a longstanding corporate partner of MIT, supporting such efforts as the <a href="">Wright Brother’s Wind Tunnel</a> renovation and the New Engineering Education Transformation <a href="">(NEET) program</a>, which focuses on modern industry and real-world projects in support of MIT’s educational mission. In 2020, Boeing is slated to open the <a href="">Aerospace and Autonomy Center</a> in Kendall Square, which will focus on advancing enabling technologies for autonomous aircraft.</p> <p>Just last spring the Institute announced a new relationship with <a href="">Blue Origin</a> in which it will begin planning and <a href="" target="_self">developing new payloads</a> for missions to the moon. These new science experiments, rovers, power systems, and more will hitch a ride to the moon via Blue Moon, Blue Origin’s flexible lunar lander.&nbsp;</p> <p>Working with IBM, MIT researchers are exploring the potential uses of artificial intelligence in space research. This year, IBM’s AI Research Week (Sept. 16-20) will feature an event, co-hosted with AeroAstro, in which researchers will pitch ideas for projects related to <a href="">AI and the International Space Station</a>.</p> <p>“We are currently in an exciting new era marked by the development and growth of entrepreneurial private enterprises driving space exploration,” says Hastings. “This will lead to new and transformative ways for human beings to travel to space, to create new profit-making ventures in space for the world’s economy, and, of course, lowering the barrier of access to space so many other countries can join this exciting new enterprise.”</p> Building on the legacy of the Apollo program, MIT faculty, staff, and students are working toward the next great advances in space flight — ones that could propel humans back to the moon, and to parts still unknown.Aeronautical and astronautical engineering, Spaceflight, Space, astronomy and planetary science, History of MIT, History, Industry, Collaboration, Additive manufacturing, 3-D printing, NASA For first time, astronomers catch asteroid in the act of changing color Asteroid is likely shedding reddish dust, revealing a fresh, blue surface beneath. Thu, 29 Aug 2019 23:59:59 -0400 Jennifer Chu | MIT News Office <p>Last December, scientists discovered an “active” asteroid within the asteroid belt, sandwiched between the orbits of Mars and Jupiter. The space rock, designated by astronomers as 6478 Gault, appeared to be leaving two trails of dust in its wake — active behavior that is associated with comets but rarely seen in asteroids.</p> <p>While astronomers are still puzzling over the cause of Gault’s comet-like activity, an MIT-led team now reports that it has caught the asteroid in the act of changing color, in the near-infrared spectrum, from red to blue. It is the first time scientists have observed a color-shifting asteroid, in real-time.</p> <p>“That was a very big surprise,” says Michael Marsset, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “We think we have witnessed the asteroid losing its reddish dust to space, and we are seeing the asteroid’s underlying, fresh blue layers.”</p> <p>Marsset and his colleagues have also confirmed that the asteroid is rocky — proof that the asteroid’s tail, though seemingly comet-like, is caused by an entirely different mechanism, as comets are not rocky but more like loose snowballs of ice and dust.</p> <p>“It’s the first time to my knowledge that we see a rocky body emitting dust, a little bit like a comet,” Marsset says. “It means that probably some mechanism responsible for dust emission is different from comets, and different from most other active main-belt asteroids.”</p> <p>Marsset and his colleagues, including EAPS Research Scientist Francesca DeMeo and Professor Richard Binzel, have published their results today in the journal <em>Astrophysical Journal Letters</em>.</p> <p><strong>A rock with tails</strong></p> <p>Astronomers first discovered 6478 Gault in 1988 and named the asteroid after planetary geologist Donald Gault. Until recently, the space rock was seen as relatively average, measuring about 2.5 miles wide and orbiting along with millions of other bits of rock and dust within the inner region of the asteroid belt, 214 million miles from the sun.</p> <p>In January, images from various observatories, including NASA’s Hubble Space Telescope, captured two narrow, comet-like tails trailing the asteroid. Astronomers estimate that the longer tail stretches half a million miles out, while the shorter tail is about a quarter as long. The tails, they concluded, must consist of tens of millions of kilograms of dust, actively ejected by the asteroid, into space. But how? The question reignited interest in Gault, and studies since then have unearthed past instances of similar activity by the asteroid.</p> <p>“We know of about a million bodies between Mars and Jupiter, and maybe about 20 that are active in the asteroid belt,” Marsset says. “So this is very rare.”</p> <p>He and his colleagues joined the search for answers to Gault’s activity in March, when they secured observation time at NASA’s Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. Over two nights, they observed the asteroid and used a high-precision spectrograph to divide the asteroid’s incoming light into various frequencies, or colors, the relative intensities of which can give scientists an idea of an object’s composition.</p> <p>From their analysis, the team determined that the asteroid’s surface is composed mainly of silicate, a dry, rocky material, similar to most other asteroids, and, more importantly, not at all like most comets.</p> <p>Comets typically come from the far colder edges of the solar system. When they approach the sun, any surface ice instantly sublimates, or vaporizes into gas, creating the comet’s characteristic tail. Since Marsset’s team has found 6478 Gault is a dry, rocky body, this means it likely is generating dust tails by some other active mechanism.</p> <p><strong>A fresh change</strong></p> <p>As the team observed the asteroid, they discovered, to their surprise, that the rock was changing color in the near-infrared, from red to blue.</p> <p>“We've never seen such a dramatic change like this over such a short period of time,” says co-author DeMeo.</p> <p>The scientists say they are likely seeing the asteroid’s surface dust, turned red over millions of years of exposure to the sun, being ejected into space, revealing a fresh, less irradiated surface beneath, that appears blue at near-infrared wavelengths.</p> <p>“Interestingly, you only need a very thin layer to be removed to see a change in the spectrum,” DeMeo says. “It could be as thin as a single layer of grains just microns deep.”</p> <p>So what could be causing the asteroid to turn color? The team and other groups studying 6478 Gault believe the reason for the color shift, and the asteroid’s comet-like activity, is likely due to the same mechanism: a fast spin. The asteroid may be spinning fast enough to whip off layers of dust from its surface, through sheer centrifugal force. The researchers estimate it would need to have about a two-hour rotation period, spinning around every couple of hours, versus Earth’s 24-hour period.</p> <p>“About 10 percent of asteroids spin very fast, meaning with a two- to three-hour rotation period, and it’s most likely due to the sun spinning them up,” says Marsset.</p> <p>This spinning phenomenon is known as the YORP effect (or, the Yarkovsky-O’Keefe-Radzievskii-Paddack effect, named after the scientists who discovered it), which refers to the effect of solar radiation, or photons, on small, nearby bodies such as asteroids. While asteroids reflect most of this radiation back into space, a fraction of these photons is absorbed, then reemitted as heat, and also momentum. This creates a small force that, over millions of years, can cause the asteroid to spin faster.</p> <p>Astronomers have observed the YORP effect on a handful of asteroids in the past. To confirm a similar effect is acting on 6478 Gault, researchers will have to detect its spin through light curves — measurements of the asteroid’s brightness over time. The challenge will be to see through the asteroid’s considerable dust tail, which can obscure key portions of the asteroid’s light.</p> <p>Marsset’s team, along with other groups, plan to study the asteroid for further clues to activity, when it next becomes visible in the sky.</p> <p>“I think [the group’s study] reinforces the fact that the asteroid belt is a really dynamic place,” DeMeo says. “While the asteroid fields you see in the movies, all crashing into each other, is an exaggeration, there is definitely a lot happening out there every moment.”</p> <p>This research was funded, in part, by the NASA Planetary Astronomy Program.</p> The asteroid 6478 Gault is seen with the NASA/ESA Hubble Space Telescope, showing two narrow, comet-like tails of debris that tell us that the asteroid is slowly undergoing self-destruction. The bright streaks surrounding the asteroid are background stars. The Gault asteroid is located between the orbits of Mars and Jupiter.Image: NASA, ESA, K. Meech and J. Kleyna, O. HainautAstronomy, Astrophysics, EAPS, NASA, Planetary science, Research, Satellites, School of Science, Space, astronomy and planetary science A major expansion for the Green Building $60 million upgrade will add 12,000 square feet for meetings, classrooms, and study spaces. Thu, 22 Aug 2019 12:00:01 -0400 MIT Resource Development <p>Rising nearly 300 feet from the ground, the Cecil and Ida Green Building, aka <a href="" target="_blank">Building 54</a>, stands out as not only the tallest building on MIT’s campus but also (until recently) the tallest building in Cambridge, Massachusetts. Yet it’s not obvious from the outside what actually goes on within this imposing 55-year-old structure designed by the late I.M. Pei ’40.</p> <p>People on campus tours often hear about the annual pumpkin drop, or about instances when students have commandeered the Green Building’s LED-equipped windows to play giant games of Tetris. But not everyone learns about the groundbreaking work carried out inside — such as the development of chaos theory, seismic tomography, numerical weather prediction, climate modeling, and far-reaching NASA missions.</p> <p>This is the headquarters of MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS), and plans are now underway to give Building 54 a major facelift, including a new LEED-certified addition that will offer a window into the important work taking place inside.</p> <p>The $60 million upgrade will allow construction of an Earth and Environment Pavilion designed to be a vital center for environmental and climate research on MIT’s campus. With assistance from the Institute and generous private donors — including John H. Carlson; George Elbaum ’59, SM ’63, PhD ’67; Fred A. Middleton Jr. ’71; Neil Pappalardo ’64; and Shell — EAPS recently passed the midway point on its $30 million fundraising campaign for the new pavilion and other improvements to the Green Building, such as a renovated lecture hall (54-100) to be renamed the Shell Auditorium.</p> <p>The project will yield about 12,000 square feet of additional space, providing new meeting places, classrooms, and study areas. The enlarged and revamped Green Building is expected to help EAPS attract and retain top faculty and students. But the more ambitious objective is to enhance the research undertaken within the department by co-locating EAPS and the MIT-Woods Hole Oceanographic Institution Joint Program with the MIT Environmental Solutions Initiative, affording greater opportunities for interaction and the cross-pollination of ideas.</p> <p><em>This article originally appeared in <a href="" target="_blank">MIT Spectrum</a>. </em></p> An artist’s rendering depicts the Green Building (Building 54), home to the MIT Department of Earth, Atmospheric and Planetary Sciences, with the planned Earth and Environment Pavilion.Image: EllenzweigEAPS, Woods Hole, Campus buildings and architecture, Design, Earth and atmospheric sciences, Space, astronomy and planetary science, School of Science, Alumni/ae, ESI, Giving A battery-free sensor for underwater exploration Submerged system uses the vibration of “piezoelectric” materials to generate power and send and receive data. Tue, 20 Aug 2019 08:59:59 -0400 Rob Matheson | MIT News Office <p>To investigate the vastly unexplored oceans covering most our planet, researchers aim to build a submerged network of interconnected sensors that send data to the surface — an underwater “internet of things.” But how to supply constant power to scores of sensors designed to stay for long durations in the ocean’s deep?</p> <p>MIT researchers have an answer: a battery-free underwater communication system that uses near-zero power to transmit sensor data. The system could be used to monitor sea temperatures to study climate change and track marine life over long periods — and even sample waters on distant planets. They are presenting the system at the SIGCOMM conference this week, in a paper that has won the conference’s “best paper” award.</p> <p>The system makes use of two key phenomena. One, called the “piezoelectric effect,” occurs when vibrations in certain materials generate an electrical charge. The other is “backscatter,” a communication technique commonly used for RFID tags, that transmits data by reflecting modulated wireless signals off a tag and back to a reader.</p> <p>In the researchers’ system, a transmitter sends acoustic waves through water toward a piezoelectric sensor that has stored data. When the wave hits the sensor, the material vibrates and stores the resulting electrical charge. Then the sensor uses the stored energy to reflect a wave back to a receiver — or it doesn’t reflect one at all. Alternating between reflection in that way corresponds to the bits in the transmitted data: For a reflected wave, the receiver decodes a 1; for no reflected wave, the receiver decodes a 0.</p> <p>“Once you have a way to transmit 1s and 0s, you can send any information,” says co-author Fadel Adib, an assistant professor in the MIT Media Lab and the Department of Electrical Engineering and Computer Science and founding director of the Signal Kinetics Research Group. “Basically, we can communicate with underwater sensors based solely on the incoming sound signals whose energy we are harvesting.”</p> <p>The researchers demonstrated their Piezo-Acoustic Backscatter System in an MIT pool, using it to collect water temperature and pressure measurements. The system was able to transmit 3 kilobits per second of accurate data from two sensors simultaneously at a distance of 10 meters between sensor and receiver.</p> <p>Applications go beyond our own planet. The system, Adib says, could be used to collect data in the recently discovered subsurface ocean on Saturn’s largest moon, Titan. In June, NASA announced the Dragonfly mission to send a rover in 2026 to explore the moon, sampling water reservoirs and other sites.</p> <p>“How can you put a sensor under the water on Titan that lasts for long periods of time in a place that’s difficult to get energy?” says Adib, who co-wrote the paper with Media Lab researcher JunSu Jang. “Sensors that communicate without a battery open up possibilities for sensing in extreme environments.”</p> <p><div class="cms-placeholder-content-video"></div></p> <p><strong>Preventing deformation</strong></p> <p>Inspiration for the system hit while Adib was watching “Blue Planet,” a nature documentary series exploring various aspects of sea life. Oceans cover about 72 percent of Earth’s surface. “It occurred to me how little we know of the ocean and how marine animals evolve and procreate,” he says. Internet-of-things (IoT) devices could aid that research, “but underwater you can’t use Wi-Fi or Bluetooth signals … and you don’t want to put batteries all over the ocean, because that raises issues with pollution.”</p> <p>That led Adib to piezoelectric materials, which have been around and used in microphones and other devices for about 150 years. They produce a small voltage in response to vibrations. But that effect is also reversible: Applying voltage causes the material to deform. If placed underwater, that effect produces a pressure wave that travels through the water. They’re often used to detect sunken vessels, fish, and other underwater objects.</p> <p>“That reversibility is what allows us to develop a very powerful underwater backscatter communication technology,” Adib says.</p> <p>Communicating relies on preventing the piezoelectric resonator from naturally deforming in response to strain. At the heart of the system is a submerged node, a circuit board that houses a piezoelectric resonator, an energy-harvesting unit, and a microcontroller. Any type of sensor can be integrated into the node by programming the microcontroller. An acoustic projector (transmitter) and underwater listening device, called a hydrophone (receiver), are placed some distance away.</p> <p>Say the sensor wants to send a 0 bit. When the transmitter sends its acoustic wave at the node, the piezoelectric resonator absorbs the wave and naturally deforms, and the energy harvester stores a little charge from the resulting vibrations. The receiver then sees no reflected signal and decodes a 0.</p> <p>However, when the sensor wants to send a 1 bit, the nature changes. When the transmitter sends a wave, the microcontroller uses the stored charge to send a little voltage to the piezoelectric resonator. That voltage reorients the material’s structure in a way that stops it from deforming, and instead reflects the wave. Sensing a reflected wave, the receiver decodes a 1.</p> <p><strong>Long-term deep-sea sensing</strong></p> <p>The transmitter and receiver must have power but can be planted on ships or buoys, where batteries are easier to replace, or connected to outlets on land. One transmitter and one receiver can gather information from many sensors covering one area or many areas.</p> <p>“When you’re tracking a marine animal, for instance, you want to track it over a long range and want to keep the sensor on them for a long period of time. You don’t want to worry about the battery running out,” Adib says. “Or, if you want to track temperature gradients in the ocean, you can get information from sensors covering a number of different places.”</p> <p>Another interesting application is monitoring brine pools, large areas of brine that sit in pools in ocean basins, and are difficult to monitor long-term. They exist, for instance, on the Antarctic Shelf, where salt settles during the formation of sea ice, and could aid in studying melting ice and marine life interaction with the pools. “We could sense what’s happening down there, without needing to keep hauling sensors up when their batteries die,” Adib says.</p> <p>Polly Huang, a professor of electrical engineering at Taiwan National University, praised the work for its technical novelty and potential impact on environmental science. “This is a cool idea,” Huang says. “It's not news one uses piezoelectric crystals to harvest energy … [but is the] first time to see it being used as a radio at the same time [which] is unheard of to the sensor network/system research community. Also interesting and unique is the hardware design and fabrication. The circuit and the design of the encapsulation are both sound and interesting.”</p> <p>While noting that the system still needs more experimentation, especially in sea water, Huang adds that “this might be the ultimate solution for researchers in marine biography, oceanography, or even meteorology — those in need of long-term, low-human-effort underwater sensing.”</p> <p>Next, the researchers aim to demonstrate that the system can work at farther distances and communicate with more sensors simultaneously. They’re also hoping to test if the system can transmit sound and low-resolution images.</p> <p>The work is sponsored, in part, by the U.S Office of Naval Research.</p> A battery-free underwater “piezoelectric” sensor invented by MIT researchers transmits data by absorbing or reflecting sound waves back to a receiver, where a reflected wave decodes a 1 bit and an absorbed wave decodes a 0 bit — and simultaneously stores energy.Image courtesy of the researchers Research, Computer science and technology, Water, Sensors, Wireless, Oceanography and ocean engineering, Media Lab, Electrical Engineering & Computer Science (eecs), School of Engineering, School of Architecture and Planning, Planetary science, Astronomy, space and planetary science Physicists design an experiment to pin down the origin of the elements With help from next-generation particle accelerators, the approach may nail down the rate of oxygen production in the universe. Tue, 20 Aug 2019 00:00:00 -0400 Jennifer Chu | MIT News Office <p>Nearly all of the oxygen in our universe is forged in the bellies of massive stars like our sun. As these stars contract and burn, they set off thermonuclear reactions within their cores, where nuclei of carbon and helium can collide and fuse in a rare though essential nuclear reaction that generates much of the oxygen in the universe.</p> <p>The rate of this oxygen-generating reaction has been incredibly tricky to pin down. But if researchers can get a good enough estimate of what’s known as the “radiative capture reaction rate,” they can begin to work out the answers to fundamental questions, such as the ratio of carbon to oxygen in the universe. An accurate rate might also help them determine whether an exploding star will settle into the form of a black hole or a neutron star. &nbsp;</p> <p>Now physicists at MIT’s Laboratory for Nuclear Science (LNS) have come up with an experimental design that could help to nail down the rate of this oxygen-generating reaction. The approach requires a type of particle accelerator that is still under construction, in several locations around the world. Once up and running, such “multimegawatt” linear accelerators may provide just the right conditions to run the oxgen-generating reaction in reverse, as if turning back the clock of star formation.</p> <p>The researchers say such an “inverse reaction” should give them an estimate of the reaction rate that actually occurs in stars, with higher accuracy than has previously been achieved.</p> <p>“The job description of a physicist is to understand the world, and right now, we don’t quite understand where the oxygen in the universe comes from, and, how oxygen and carbon are made,” says Richard Milner, professor of physics at MIT. “If we’re right, this measurement will help us answer some of these important questions in nuclear physics regarding the origin of the elements.”</p> <p>Milner is a co-author of a paper appearing today in the journal <em>Physical Review C</em>, along with lead author and MIT-LNS postdoc Ivica Friščić and MIT Center for Theoretical Physics Senior Research Scientist T. William Donnelly.</p> <p><strong>A precipitous drop</strong></p> <p>The radiative capture reaction rate refers to the reaction between a carbon-12 nucleus and a helium nucleus, also known as an alpha particle, that takes place within a star. When these two nuclei collide, the carbon nucleus effectively “captures” the alpha particle, and in the process, is excited and radiates energy in the form of a photon. What’s left behind is an oxygen-16 nucleus, which ultimately decays to a stable form of oxygen that exists in our atmosphere.</p> <p>But the chances of this reaction occurring naturally in a star are incredibly slim, due to the fact that both an alpha particle and a carbon-12 nucleus are highly positively charged. If they do come in close contact, they are naturally inclined to repel, in what’s known as a Coulomb’s force. To fuse to form oxygen, the pair would have to collide at sufficiently high energies to overcome Coulomb’s force — a rare occurrence. Such an exceedingly low reaction rate would be impossible to detect at the energy levels that exist within stars.</p> <p>For the past five decades, scientists have attempted to simulate the radiative capture reaction rate, in small yet powerful particle accelerators. They do so by colliding beams of helium and carbon in hopes of fusing nuclei from both beams to produce oxygen. They have been able to measure such reactions and calculate the associated reaction rates. However, the energies at which such accelerators collide particles are far higher than what occurs in a star, so much so that the current estimates of the oxygen-generating reaction rate are difficult to extrapolate to what actually occurs within stars.</p> <p>“This reaction is rather well-known at higher energies, but it drops off precipitously as you go down in energy, toward the interesting astrophysical region,” Friščić says.</p> <p><strong>Time, in reverse</strong></p> <p>In the new study, the team decided to resurrect a previous notion, to produce the inverse of the oxygen-generating reaction. The aim, essentially, is to start from oxygen gas and split its nucleus into its starting ingredients: an alpha particle and a carbon-12 nucleus. The team reasoned that the probability of the reaction happening in reverse should be greater, and therefore more easily measured, than the same reaction run forward. The inverse reaction should also be possible at energies nearer to the energy range within actual stars.</p> <p>In order to split oxygen, they would need a high-intensity beam, with a super-high concentration of electrons. (The more electrons that bombard a cloud of oxygen atoms, the more chance there is that one electron among billions will have just the right energy and momentum to collide with and split an oxygen nucleus.)</p> <p>The idea originated with fellow MIT Research Scientist Genya Tsentalovich, who led a proposed experiment at the MIT-Bates South Hall electron storage ring in 2000.&nbsp; Although the experiment was never carried out at the Bates accelerator, which ceased operation in 2005, Donnelly and Milner felt the idea merited to be studed in detail. With the initiation of construction of next-generation linear accelerators in Germany and at Cornell University, having the capability to produce electron beams of high enough intensity, or current, to potentially trigger the inverse reaction, and the arrival of Friščić at MIT in 2016, the study got underway.</p> <p>“The possibility of these new, high-intensity electron machines, with tens of milliamps of current, reawakened our interest in this [inverse reaction] idea,” Milner says.</p> <p>The team proposed an experiment to produce the inverse reaction by shooting a beam of electrons at a cold, ultradense cloud of oxygen. If an electron successfully collided with and split an oxygen atom, it should scatter away with a certain amount of energy, which physicists have previously predicted. The researchers would isolate the collisions involving electrons within this given energy range, and from these, they would isolate the alpha particles produced in the aftermath.</p> <p>Alpha particles are produced when O-16 atoms split. The splitting of other oxygen isotopes can also result in alpha particles, but these would scatter away slightly faster — about 10 nanoseconds faster — than alpha particles produced from the splitting of O-16 atoms. So, the team reasoned they would isolate those alpha particles that were slightly slower, with a slightly shorter “time of flight.”</p> <p>The researchers could then calculate the rate of the inverse reaction, given how often slower alpha particles — and by proxy, the splitting of O-16 atoms — occurred. They then developed a model to relate the inverse reaction to the direct, forward reaction of oxygen production that naturally occurs in stars.</p> <p>“We’re essentially doing the time-reverse reaction,” Milner says. “If you measure that at the precision we’re talking about, you should be able to directly extract the reaction rate, by factors of &nbsp;up to 20 beyond what anybody has done in this region.”</p> <p>Currently, a multimegawatt linear accerator, MESA, is under construction in Germany. &nbsp;Friščić and Milner are collaborating with physicists there to design the experiment, in hopes that, once up and running, they can put their experiment into action to truly pin down the rate at which stars churn oxygen out into the universe.</p> <p>“If we’re right, and we make this measurement, it will allow us to answer how much carbon and oxygen is formed in stars, which is the largest uncertainty that we have in our understanding of how stars evolve,” Milner says.</p> <p>This research was carried out at MIT’s Laboratory for Nuclear Science and was supported, in part, by the U.S. Department of Energy Office of Nuclear Physics.</p> A new experiment designed by MIT physicists may help to pin down the rate at which huge, massive stars produce oxygen in the universe.Image: NASA/ESA/HubbleBlack holes, Center for Theoretical Physics, Laboratory for Nuclear Science, Nuclear science and engineering, Physics, Research, School of Science, Space, astronomy and planetary science Rocky, Earth-sized exoplanet is missing an atmosphere Study reports on search for an atmosphere around a planet somewhat similar to ours. Mon, 19 Aug 2019 11:00:00 -0400 Jennifer Chu | MIT News Office <p>Astronomers at MIT, Harvard University, and elsewhere have searched a rocky, Earth-sized exoplanet for signs of an atmosphere — and found none.</p> <p>Atmospheres have previously been detected on planets much larger than our own, including several hot-Jupiters and sub-Neptunes, all of which are primarily made of ice and gas. But this is the first time scientists have been able to nail down whether an Earth-sized, terrestrial planet outside our solar system has an atmosphere.</p> <p>The planet in question, LHS 3844b, was discovered in 2018 by NASA’s Transiting Exoplanet Survey Satellite, TESS, and was measured to be about 1.3 times larger than Earth. The planet zips around its star in just 11 hours, making it one of the fastest orbiting exoplanets known. The star itself is a small, cool M-dwarf that resides just 49 light-years from Earth.</p> <p>In a paper published today in <em>Nature</em>, the team reports that LHS 3844b likely has neither a thick, Venus-like atmosphere nor a thin, Earth-like atmosphere. Instead, the planet is probably more similar to Mercury — a blistering, bare rock. If an atmosphere ever existed, the researchers say the star’s radiation likely blasted it away early in the planet’s formation.</p> <p>“We basically found a hot planet with no gases around it,” says co-author Daniel Koll, a postdoc in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. “This is the first time we’ve known anything in detail about the atmosphere of a planet around these M-dwarfs, which are the most common type of star, making LHS 3844b the most common type of rocky planet in the galaxy.”&nbsp;</p> <p>Could any form of life manage to take hold in such a barren wasteland? Koll and his colleagues say it’s extremely unlikely, as the lack of an atmosphere would instantly cook off any organisms on the planet’s surface. But that doesn’t mean other terrestrial exoplanets are similarly without cover.</p> <p>“We never thought this particular planet would be hospitable for life,” says lead author Laura Kreidberg, a researcher at the Harvard Center for Astrophysics. “It’s more a question of whether this whole category of planets around smaller stars has atmospheres or not. And our technique is a robust way of assessing whether an atmosphere is present or not.”</p> <p>Kreidberg and Koll’s co-authors from MIT include Jason Dittmann, Ian Crossfield, David Berardo, Xueying “Sherry” Guo, George Ricker, Sara Seager, and Roland Vanderspek, along with colleagues from Harvard, the University of Texas at Austin, the Jet Propulsion Laboratory, Caltech, Stanford University, the University of Maryland, and Vanderbilt University.</p> <div class="cms-placeholder-content-video"></div> <p><strong>Faces exposed</strong></p> <p>In 2018, LHS 3844b was among the first crop of extrasolar worlds confirmed by TESS, an <a href="">MIT-developed satellite</a> that monitors thousands of the closest, brightest stars, for transits — periodic dips in starlight that could signal a planet orbiting in front of the star, momentarily blocking its light.</p> <p>Kreidberg and her team flagged LHS 3844b as an ideal laboratory, as its star is bright and nearby, and therefore a source against which scientists could study the planet in detail. As LHS 3844b is extremely close to its star, and thus incredibly hot, Kreidberg and Koll reasoned that it should give off enough heat to reveal clues as to whether it hosts an atmosphere.</p> <p><img alt="" src="/sites/" style="width: 500px; height: 500px;" /></p> <p><span style="font-size:10px;"><em>Cartoon illustrating the brightness measured over time (white line) corresponding to a tidally locked planet orbiting its parent star. The brightness increases as the planet’s hot dayside rotates into view. Image: Laura Kreidberg</em></span></p> <p>LHS 3844b is a tidally locked planet, meaning that it has a permanent day side and night side to its star, just as the moon always shows the same face to the Earth. If an atmosphere exists, it would circulate heat around the entire planet, and the heat emitted by both the day and night sides would be roughly the same. In the absence of an atmosphere, the day side would be considerably hotter than the night side.</p> <p>As the planet orbits its star, an observer can see various faces of that planet.&nbsp; As it comes out from behind its star, the planet’s day side is exposed. Then, as it circles in front of the star, the planet swivels to show its night side, before coming back around to expose its day side before crossing behind the star again.</p> <p>The researchers figured that if they could measure the heat given off by the planet’s various faces during its orbit, they could determine the temperature difference between the day side and night side, and ultimately, whether the planet has an atmosphere.</p> <p>To test this idea, the team used NASA’s Spitzer Space Telescope, an instrument that measures infrared radiation, or heat, and pointed the telescope at LHS 3844b for 100 hours, capturing about 10 orbits of the planet in total. They measured the heat given off by the planet’s various faces throughout each orbit.</p> <p>“This has been done a lot for planets closer in size to Jupiter, but this is the very first time that this measurement has ever been made for a terrestrial planet around an M dwarf star,” Koll says.</p> <p><strong>“Somewhere out there”</strong></p> <p>From their measurements, the researchers calculated that the dayside is a toasty 1,000 kelvins, or about 1,340 degrees Fahrenheit, whereas the nightside plummets to as low as 0 K, or -460 F. The drastic temperature difference indicates that the planet does not have a thick, Venus-like atmosphere that would distribute heat evenly around the entire planet.</p> <p>The team simulated various scenarios involving thinner atmospheres of different compositions, but they found that none produced a heat distribution that matched their observations, indicating that the planet also does not host a thin, Earth-like atmosphere.</p> <p>There was one scenario in which an extremely thin atmosphere, similar to that of Mars, could produce the planet’s drastic heat difference. However, the team found that it was unlikely that such a thin atmosphere could remain stable, as the star’s radiation would quickly blast away any trace gases surrounding the planet.</p> <p>The researchers have concluded that LHS 3844b is essentially a super-hot, bare rock. But what type of rock could it be? In one last step, the team looked to identify its composition by measuring the reflectivity of the planet’s surface. As we know on Earth, different minerals reflect light to various degrees — basalt, which is black, solidified lava, reflects very little light, whereas lighter-colored rocks like granite, containing minerals such as quartz, have a higher reflectivity. The team measured the ratio of the star’s brightness with that of the planet’s in order to calculate the planet’s reflectivity.</p> <p>“We can see a granite-like surface is ruled out by our data, whereas a dark material like a lava field in Hawaii, or the lunar mare, or like the surface of Mercury, is consistent with our observations,” Kreidberg says.</p> <p>While the group concluded there is an absence of any atmosphere — and, therefore, life — on LHS 3844b, they say this may not be the case for similar terrestrial exoplanets orbiting cool M-dwarfs. They hope to apply their technique to other rocky exoplanets, including ones that are further out from their stars and have a better chance of retaining an atmosphere.</p> <p>“Atmospheres help protect life and shield it from ultraviolet radiation,” Kreidberg says. “I would be thrilled to detect an atmosphere on a planet, even if it’s a little too hot or too cold, because that would tell us, yes, some terrestrial exoplanets can have atmospheres, and probably somewhere out there, there’s going to be one that’s the right temperature, that has been able to keep liquid water.”</p> Artist’s rendering of the surface of LHS 3844b, a planet that has been found to have no atmosphere.Image: NASA/JPL-Caltech/R. Hurt (IPAC)Astronomy, Astrophysics, Kavli Institute, NASA, Planetary science, Research, Satellites, School of Science, Space, astronomy and planetary science, Stars Data-mining for dark matter Tracy Slatyer hunts through astrophysical data for clues to the invisible universe. Thu, 15 Aug 2019 23:59:59 -0400 Jennifer Chu | MIT News Office <p>When Tracy Slatyer faced a crisis of confidence early in her educational career, Stephen Hawking’s “A Brief History of Time” and a certain fictional janitor at MIT helped to bolster her resolve.</p> <p>Slatyer was 11 when her family moved from Canberra, Australia, to the island nation of Fiji. It was a three-year stay, as part of her father’s work for the South Pacific Forum, an intergovernmental organization.</p> <p>“Fiji was quite a way behind the U.S. and Australia in terms of gender equality, and for a girl to be interested in math and science carried noticeable social stigma,” Slatyer recalls. “I got bullied quite a lot.”</p> <p>She eventually sought guidance from the school counselor, who placed the blame for the bullying on the victim herself, saying that Slatyer wasn’t sufficiently “feminine.” Slatyer countered that the bullying seemed to be motivated by the fact that she was interested in and good at math, and she recalls the counselor’s unsympathetic advice: “Well, yes, honey, that’s a problem you can fix.”</p> <p>“I went home and thought about it, and decided that math and science were important to me,” Slatyer says. “I was going to keep doing my best to learn more, and if I got bullied, so be it.”</p> <p>She doubled down on her studies and spent a lot of time at the library; she also benefited from supportive parents, who gave her Hawking’s groundbreaking book on the origins of the universe and the nature of space and time.</p> <p>“It seemed like the language in which these ideas could most naturally be described was that of mathematics,” Slatyer says. “I knew I was pretty good at math. And learning that that talent was potentially something I could apply to understanding how the universe worked, and maybe how it began, was very exciting to me.”</p> <p>Around this same time, the movie “Good Will Hunting” came out in theaters. The story, of a townie custodian at MIT who is discovered as a gifted mathematician, had a motivating impact on Slatyer.</p> <p>“What my 13-year-old self took out of this was, MIT was a place where, if you were talented at math, people would see that as a good thing rather than something to be stigmatized, and make you welcome — even if you were a janitor or a little girl from Fiji,” Slatyer says. “It was my first real indication that such places might exist. Since then, MIT has been an important symbol to me, of valuing intellectual inquiry and being willing to accept anyone in the world.”</p> <p>This year, Slatyer received tenure at MIT and is now the Jerrold R. Zacharias Associate Professor of Physics and a member of the Center for Theoretical Physics and the Laboratory for Nuclear Science. She focuses on searching through telescope data for signals of mysterious phenomena such as dark matter, the invisible stuff that makes up more than 80 percent of the matter in the universe but has only been detected through its gravitational pull. In her teaching, she seeks to draw out and support a new and diverse crop of junior scientists.</p> <p>“If you want to understand how the universe works, you want the very best and brightest people,” Slatyer says. “It’s essential that theoretical physics becomes more inclusive and welcoming, both from a moral perspective and to get the best science done.”</p> <p><strong>Connectivity</strong></p> <p>Slatyer’s family eventually moved back to Canberra, where she dove eagerly into the city’s educational opportunities.</p> <p>After earning an undergraduate degree from the Australian National University, followed by a brief stint at the University of Melbourne, Slatyer was accepted to Harvard University as a physics graduate student. Her interests were slowly gravitating toward particle physics, but she was unsure about which direction to take. Then, two of her mentors put her in touch with a junior faculty member, Doug Finkbeiner, who was leading a project to mine astrophysical data for signals of new physics.</p> <p>At the time, much of the physics community was eagerly anticipating the start-up of the Large Hadron Collider and the release of data on particle interactions at high energies, which could potentially reveal physics beyond the Standard Model.</p> <p>In contrast, telescopes have long made public their own data on astrophysical phenomena. What if, instead of looking through these data for objects such as black holes and neutron stars that evolved over millions of years, one could comb through it for signals of more fundamental mysteries, such as hints of new elementary particles and even dark matter?</p> <p>The prospects were new and exciting, and Slatyer promptly took on the challenge.</p> <p><strong>“Chasing that feeling”</strong></p> <p>In 2008, the Fermi Gamma-Ray Space Telescope launched, giving astronomers a new view of the cosmos in the gamma-ray band of the electromagnetic spectrum, where high-energy astrophysical phenomena can be seen. Slatyer and Finkbeiner proposed that Fermi’s data might also reveal signals of dark matter, which could theoretically produce high-energy electrons when dark matter particles collide.</p> <p>In 2009, Fermi made its data available to the public, and Slatyer and Finkbeiner —together with Harvard postdoc Greg Dobler and collaborators at New York University — put their mining tools to work as soon as the data were released online.</p> <p>The group eventually constructed a map of the Milky Way galaxy, shining in gamma rays, and revealed a fuzzy, egg-like shape. Upon further analysis, led by Slatyer’s fellow PhD student Meng Su, this fuzzy “haze” coalesced into a figure-eight, or double-bubble structure, extending some 25,000 light-years above and below the disc of the Milky Way. Such a structure had never been observed before. The group named the mysterious structure the “Fermi bubbles,” after the telescope that originally observed it.</p> <p>“It was really special — we were the first people in the history of the world to be able to look at the sky in this way and understand that this structure was there,” Slatyer says. “That’s a really incredible feeling, and chasing that feeling is something that inspires and motivates me, and I think many scientists.”</p> <p><strong>Searching for the invisible</strong></p> <p>Today, Slatyer continues to sift through Fermi data for evidence of dark matter. The Fermi Bubbles’ distinctive shape makes it unlikely they are associated with dark matter; they are more likely to reveal a past eruption from the giant black hole at the Milky Way’s center, or outflows fueled by exploding stars. However, other signals are more promising.</p> <p>Around the center of the Milky Way, where dark matter is thought to concentrate, there is a glow of gamma rays. In 2013, Slatyer, her first PhD student Nicholas Rodd, and collaborators at Harvard University and Fermilab showed this glow had properties similar to what theorists would expect if dark matter particles were colliding and producing visible light. However, in 2015, Slatyer and collaborators at MIT and Princeton University challenged this interpretation with a new analysis, showing that the glow was more consistent with originating from a new population of spinning neutron stars called pulsars.</p> <p>But the case is not quite closed. Recently, Slatyer and MIT postdoc Rebecca Leane reanalyzed the same data, this time injecting a fake dark matter signal into the data, to see whether the techniques developed in 2015 could detect dark matter if it were there. But the signal was missed, suggesting that if there were other, actual signals of dark matter in the Fermi data, they could have been missed as well.</p> <p>Slatyer is now improving on data mining techniques to better detect dark matter in the Fermi data, along with other astrophysical open data. But she won’t be discouraged if her search comes up empty.</p> <p>“There’s no guarantee there is a dark matter signal,” Slatyer says. “But if you never look, you’ll never know. And in searching for dark matter signals in these datasets, you learn other things, like that our galaxy contains giant gamma-ray bubbles, and maybe a new population of pulsars, that no one ever knew about. If you look closely at the data, the universe will often tell you something new.”</p> Associate professor Tracy Slatyer focuses on searching through telescope data for signals of mysterious phenomena such as dark matter, the invisible stuff that makes up more than 80 percent of the matter in the universe but has only been detected through its gravitational pull. In her teaching, she seeks to draw out and support a new and diverse crop of junior scientists.Images: Bryce VickmarkAstronomy, Astrophysics, Data, Center for Theoretical Physics, Faculty, Laboratory for Nuclear Science, Physics, Research, School of Science, Diversity and inclusion John Ball, longtime Haystack Observatory scientist, dies at 83 Won Rumford Medal in 1971 for his pioneering work in very long baseline astronomy. Thu, 15 Aug 2019 16:35:01 -0400 Nancy Wolfe Kotary | Haystack Observatory <p>Former MIT Haystack Observatory scientist John Allen Ball died Aug. 6 at age 83, of complications resulting from Alzheimer’s disease.</p> <p>Ball was born in 1935 at his family’s home in Ravenna, Nebraska. He graduated from the University of Nebraska at Lincoln in 1957 with a BS in electrical engineering and served for two years as a lieutenant in the U.S. Air Force in Libya.</p> <p>After returning from Libya, Ball earned a PhD in astrophysics from Harvard University, and launched his career as a radio astronomer at Harvard, first at the Harvard College Observatory in Harvard, Massachusetts, and later at Harvard’s Center for Astrophysics and its radio astronomy station in Fort Davis, Texas. Ball also taught astronomy at Worcester State College.</p> <p>In 1984, Ball joined MIT Haystack Observatory in Westford, Massachusetts, where he worked as a research scientist until his retirement in 2006. At Haystack, he worked with the 37-meter-diameter radio telescope, part of a global network of very long baseline interferometry (VLBI) experiments, and was instrumental in making the Haystack 37-meter antenna available for radio astronomy. Ball was a member of the MIT group that was awarded the prestigious Rumford Medal, along with groups from Canada and the NRAO-Cornell, by the American Academy of Arts and Sciences for pioneering work in VLBI in April 1971.</p> <p>Colleagues from MIT Haystack Observatory share very fond memories of Ball as a co-worker and friend. Michael Titus remembers him as an enthusiastic “Renaissance man who was always trying to find clever ways to help people solve problems or make their lives safer, better, or easier.” Director Colin Lonsdale says, “He was bright, articulate, and curious about all things, and one of his crusades was to make the case, whenever and wherever he could, for curiosity-driven science.”</p> <p>Throughout his career, Ball published extensively in astrophysics. Other publications include the book "Algorithms for RPM Calculators"<em> </em>(1978), as well as “The Zoo Hypothesis” (1973) and “The Search for Extraterrestrial Life: Recent Developments” (1985).</p> <p>Ball had a wide range of interests, including civil rights activism, photography, motorcycling (from Ducatis to BMWs, as seen in the slideshow above), sailing, poetry reading and writing, classical music appreciation, sushi making, and veganism. He organized a film series on nutrition, which was shown on the local cable station. He also served on the Town of Harvard Cable Committee and helped with videotaping town meetings.</p> <p>He died peacefully at his home in Harvard, Massachusetts, surrounded by family. He is survived by his wife of 64 years, Audrey Roth Ball; daughters Fifine, Desirée, and Laurie; son Kevin (Teresa Gudger); nephew Michael Ball (Beth); grandchildren Justin Walsh, Daniel Walsh, Jessica Anderson (Duke), Audrey Lewis, Lindsey Champion (Corey), and Samantha Gudger; and great-grandchildren Brookelan Heck and Tucker Ray Champion.&nbsp;</p> <p>A memorial service will be held on a date to be announced. In lieu of flowers, donations in his name may be sent to <a href="">the Alzheimer’s Association</a>.</p> John Allen Ball, MIT Haystack ObservatoryPhoto: Audrey BallHaystack Observatory, Obituaries, Staff, Space, astronomy and planetary science The music of the spheres MIT hosts &quot;Songs from Extrasolar Spaces,&quot; a musical melding of art and science inspired by the Transiting Exoplanet Survey Satellite (TESS). Fri, 09 Aug 2019 13:25:01 -0400 Ken Shulman | Arts at MIT <p>Space has long fascinated poets, physicists, astronomers, and science fiction writers. Musicians, too, have often found beauty and meaning in the skies above. At MIT’s Kresge Auditorium, a group of composers and musicians manifested their fascination with space in a concert titled “Songs from Extrasolar Spaces.” Featuring the Lorelei Ensemble — a Boston, Massachusetts-based women’s choir — the concert included premieres by MIT composers John Harbison and Elena Ruehr, along with compositions by Meredith Monk and Molly Herron. All the music was inspired by discoveries in astronomy.</p> <p>“Songs from Extrasolar Spaces,” part of an MIT conference on TESS — the Transiting Exoplanet Survey Satellite, launched in April 2018. TESS is an MIT-led NASA mission that scans the skies for evidence of exoplanets: bodies ranging from dwarf planets to giant planets that orbit stars other than our sun. During its two-year mission, TESS and its four highly-sensitive cameras survey 85 percent of the sky, monitoring more than 200,000 stars for the temporary dips in brightness that might signal a transit — the passage of a planetary body across that star.</p> <p>“There is a feeling you get when you look at these images from TESS,” says Ruehr, an award-winning MIT lecturer in the Music and Theater Arts Section and former Guggenheim Fellow. “A sense of vastness, of infinity. This is the sensation I tried to capture and transpose into vocal music.”&nbsp;</p> <p>Supported by the MIT Center for Art, Science and Technology’s Fay Chandler Creativity Grant; MIT Music and Theater Arts; and aerospace and technology giant Northrop Grumman, which also built the TESS satellite, the July 30 concert was conceived by MIT Research Associate Natalia Guerrero. Both the conference and concert marked the 50th anniversary of the Apollo 11 moon landing — another milestone in the quest to chart the universe and Earth’s place in it.</p> <p>A 2014 MIT graduate, Guerrero manages the team finding planet candidates in the TESS images at the MIT Kavli Institute for Astrophysics and Space Research and is also the lead for the MIT branch of the mission’s communications team. “I wanted to include an event that could make the TESS mission accessible to people who aren’t astronomers or physicists,” says Guerrero. “But I also wanted that same event to inspire astronomers and physicists to look at their work in a new way.”</p> <p>Guerrero majored in physics and creative writing at MIT, and after graduating she deejayed a radio show called “Voice Box” on the MIT radio station WMBR. That transmission showcased contemporary vocal music and exposed her to composers including Harbison and Ruehr. Last year, in early summer, Guerrero contacted Ruehr to gauge her interest in composing music for a still-hypothetical concert that might complement the 2019 TESS conference.</p> <p>Ruehr was keen on the idea. She was also a perfect fit for the project. The composer had often drawn inspiration from visual images and other art forms for her music. “Sky Above Clouds,” an orchestral piece she composed in 1989, is inspired by the Georgia O’Keefe paintings she viewed as a child at the Art Institute of Chicago. Ruehr had also created music inspired by David Mitchell’s visionary novel “Cloud Atlas” and Anne Patchett’s “Bel Canto.” “It’s a question of reinterpreting language, capturing its rhythms and volumes and channeling them into music,” says Ruehr. “The source language can be fiction, or painting, or in this case these dazzling images of the universe.”</p> <p>In addition, Ruehr had long been fascinated by space and stars. “My father was a mathematician who studied fast Fourier transform analysis,” says Ruehr, who is currently composing an opera set in space. “As a young girl, I’d listen to him talking about infinity with his colleagues on the telephone. I would imagine my father existing in infinity, on the edge of space.”</p> <p>Drawing inspiration from the images TESS beams back to Earth, Ruehr composed two pieces for “Songs from Extrasolar Spaces.” The first, titled “Not from the Stars,” takes its name and lyrics from a Shakespeare sonnet. For the second, “Exoplanets,” Ruehr used a text that Guerrero extrapolated from the titles of the first group of scientific papers published from TESS data. “I’m used to working from images,” explains Ruehr. “First, I study them. Then, I sit down at the piano and try to create a single sound that captures their essence and resonance. Then, I start playing with that sound.”</p> <p>Ruehr was particularly pleased to compose music about space for the Lorelei Ensemble. “There’s a certain quality in a women’s choir, especially the Lorelei Ensemble, that is perfectly suited for this project,” says Ruehr. “They have an ethereal sound and wonderful harmonic structures that make us feel as if we’re perceiving a small dab of brightness in an envelope of darkness.”</p> <p>At the 2019 MIT TESS conference, experts from across the globe shared results from the first year of observation in the sky above the Southern Hemisphere, and discussed plans for the second-year trek above the Northern Hemisphere. The composers and musicians hope “Songs from Extrasolar Spaces” brought attention to the TESS missions, offers a new perspective on space exploration, and will perhaps spark further collaborations between scientists and artists. George Ricker, TESS principal investigator; Sara Seager, TESS deputy director of science; and Guerrero presented a pre-concert lecture. “Music has the power to generate incredibly powerful emotions,” says Ruehr. “So do these images from TESS. In many ways, they are more beautiful than any stars we might ever imagine.”</p> <p>TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by Goddard Spaceflight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge; MIT Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore, Maryland. More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.</p> The Lorelei Ensemble performs in "Songs from Extrasolar Spaces: Music Inspired by TESS" on July 30 in MIT's Kresge Auditorium.Photo: Danny GoldfieldArts, Center for Art, Science and Technology, School of Humanities Arts and Social Sciences, Kavli Institute, Astronomy, NASA, TESS, Music, Faculty, School of Engineering, Satellites, Exoplanets, Theater, Special events and guest speakers, Technology and society, Space, astronomy and planetary science, Aeronautical and astronautical engineering, Alumni/ae Astrophysical shock phenomena reproduced in the laboratory Lab-scale experiment could help scientists understand interstellar and galactic-scale smashups. Tue, 06 Aug 2019 23:59:59 -0400 David L. Chandler | MIT News Office <p>Vast interstellar events where clouds of charged matter hurtle into each other and spew out high-energy particles have now been reproduced in the lab with high fidelity. The work, by MIT researchers and an international team of colleagues, should help resolve longstanding disputes over exactly what takes place in these gigantic shocks.</p> <p>Many of the largest-scale events, such as the expanding bubble of matter hurtling outward from a supernova, involve a phenomenon called collisionless shock. In these interactions, the clouds of gas or plasma are so rarefied that most of the particles involved actually miss each other, but they nevertheless interact electromagnetically or in other ways to produces visible shock waves and filaments. These high-energy events have so far been difficult to reproduce under laboratory conditions that mirror those in an astrophysical setting, leading to disagreements among physicists as to the mechanisms at work in these astrophysical phenomena.</p> <p>Now, the researchers have succeeded in reproducing critical conditions of these collisionless shocks in the laboratory, allowing for detailed study of the processes taking place within these giant cosmic smashups. The new findings are described in the journal <em>Physical Review Letters</em>, in a paper by MIT Plasma Science and Fusion Center Senior Research Scientist Chikang Li, five others at MIT, and 14 others around the world.</p> <p>Virtually all visible matter in the universe is in the form of plasma, a kind of soup of subatomic particles where negatively charged electrons swim freely along with positively charged ions instead of being connected to each other in the form of atoms. The sun, the stars, and most clouds of interstellar material are made of plasma.</p> <p>Most of these interstellar clouds are extremely tenuous, with such low density that true collisions between their constituent particles are rare even when one cloud slams into another at extreme velocities that can be much faster than 1,000 kilometers per second. Nevertheless, the result can be a spectacularly bright shock wave, sometimes showing a great deal of structural detail including long trailing filaments.</p> <p>Astronomers have found that many changes take place at these shock boundaries, where physical parameters “jump,” Li says. But deciphering the mechanisms taking place in collisionless shocks has been difficult, since the combination of extremely high velocities and low densities has been hard to match on Earth.</p> <p>While collisionless shocks had been predicted earlier, the first one that was directly identified, in the 1960s, was the bow shock formed by the solar wind, a tenuous stream of particles emanating from the sun, when it hits Earth’s magnetic field. Soon, many such shocks were recognized by astronomers in interstellar space. But in the decades since, “there has been a lot of simulations and theoretical modeling, but a lack of experiments” to understand how the processes work, Li says.</p> <p>Li and his colleagues found a way to mimic the phenomena in the laboratory by generating a jet of low-density plasma using a set of six powerful laser beams, at the OMEGA laser facility at the University of Rochester, and aiming it at a thin-walled polyimide plastic bag filled with low-density hydrogen gas. The results reproduced many of the detailed instabilities observed in deep space, thus confirming that the conditions match closely enough to allow for detailed, close-up study of these elusive phenomena. A quantity called the mean free path of the plasma particles was measured as being much greater than the widths of the shock waves, Li says, thus meeting the formal definition of a collisionless shock.</p> <p>At the boundary of the lab-generated collisionless shock, the density of the plasma spiked dramatically. The team was able to measure the detailed effects on both the upstream and downstream sides of the shock front, allowing them to begin to differentiate the mechanisms involved in the transfer of energy between the two clouds, something that physicists have spent years trying to figure out. The results are consistent with one set of predictions based on something called the Fermi mechanism, Li says, but further experiments will be needed to definitively rule out some other mechanisms that have been proposed.</p> <p>“For the first time we were able to directly measure the structure” of important parts of the collisionless shock, Li says. “People have been pursuing this for several decades.”</p> <p>The research also showed exactly how much energy is transferred to particles that pass through the shock boundary, which accelerates them to speeds that are a significant fraction of the speed of light, producing what are known as cosmic rays. A better understanding of this mechanism “was the goal of this experiment, and that’s what we measured” Li says, noting that they captured a full spectrum of the energies of the electrons accelerated by the shock.</p> <p>"This report is the latest installment in a transformative series of experiments, annually reported since 2015, to emulate an actual astrophysical shock wave for comparison with space observations," says Mark Koepke, a professor of physics at West Virginia University and chair of the Omega Laser Facility User Group, who was not involved in the study. "Computer simulations, space observations, and these experiments reinforce the physics interpretations that are advancing our understanding of the particle acceleration mechanisms in play in high-energy-density cosmic events such as gamma-ray-burst-induced outflows of relativistic plasma."</p> <p>The international team included researchers at the University of Bordeaux in France, the Czech Academy of Sciences, the National Research Nuclear University in Russia, the Russian Academy of Sciences, the University of Rome, the University of Rochester, the University of Paris, Osaka University in Japan, and the University of California at San Diego. It was supported by the U.S. Department of Energy and the French National Research Agency.</p> An example of an interstellar collisionless shock is seen in this photo of a bow shock in the Orion Nebula.Image credit: NASA and the Hubble Heritage Team (STScI/AURA)Research, Space, astronomy and planetary science, Physics, Plasma Science and Fusion Center, Staff, School of Science, Department of Energy (DoE), Astrophysics TESS discovers three new planets nearby, including temperate “sub-Neptune” Planetary system orbiting an unusually quiet star is ideal for future habitability searches. Mon, 29 Jul 2019 10:59:59 -0400 Jennifer Chu | MIT News Office <p>NASA’s Transiting Exoplanet Survey Satellite, or TESS, has discovered three new worlds that are among the smallest, nearest exoplanets known to date. The planets orbit a star just 73 light-years away and include a small, rocky super-Earth and two sub-Neptunes — planets about half the size of our own icy giant.</p> <p>The sub-Neptune furthest out from the star appears to be within a “temperate” zone, meaning that the very top of the planet’s atmosphere is within a temperature range that could support some forms of life. However, scientists say the planet’s atmosphere is likely a thick, ultradense heat trap that renders the planet’s surface too hot to host water or life.</p> <p>Nevertheless, this new planetary system, which astronomers have dubbed TOI-270, is proving to have other curious qualities. For instance, all three planets appear to be relatively close in size. In contrast, our own solar system is populated with planetary extremes, from the small, rocky worlds of Mercury, Venus, Earth, and Mars, to the much more massive Jupiter and Saturn, and the more remote ice giants of Neptune and Uranus.</p> <p>There’s nothing in our solar system that resembles an intermediate planet, with a size and composition somewhere in the middle of Earth and Neptune. But TOI-270 appears to host two such planets: both sub-Neptunes are smaller than our own Neptune and not much larger than the rocky planet in the system.</p> <p>Astronomers believe TOI-270’s sub-Neptunes may be a “missing link” in planetary formation, as they are of an intermediate size and could help researchers determine whether small, rocky planets like Earth and more massive, icy worlds like Neptune follow the same formation path or evolve separately.</p> <p>TOI-270 is an ideal system for answering such questions, because the star itself is nearby and therefore bright, and also unusually quiet. The star is an M-dwarf, a type of star that is normally extremely active, with frequent flares and solar storms. TOI-270 appears to be an older M-dwarf that has since quieted down, giving off a steady brightness, against which scientists can measure many properties of the orbiting planets, such as their mass and atmospheric composition.</p> <p>“There are a lot of little pieces of the puzzle that we can solve with this system,” says Maximilian Günther, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research and lead author of a study published today in <em>Nature Astronomy </em>that details the discovery. “You can really do all the things you want to do in exoplanet science, with this system.”</p> <p><img alt="" src="/sites/" style="width: 500px; height: 500px;" /></p> <p><em><span style="font-size:10px;">Compare and contrast worlds in the TOI 270 system with these illustrations. Temperatures given for TOI 270 planets are equilibrium temperatures, calculated without the warming effects of any possible atmospheres.&nbsp;Credit: NASA’s Goddard Space Flight Center</span></em></p> <p><strong>A planetary pattern</strong></p> <p>Günther and his colleagues detected the three new planets after looking through measurements of stellar brightness taken by TESS. The MIT-developed satellite stares at patches of the sky for 27 days at a time, monitoring thousands of stars for possible transits — characteristic dips in brightness that could signal a planet temporarily blocking the star’s light as it passes in front of it.</p> <p>The team isolated several such signals from a nearby&nbsp; star, located 73 light years away in the southern sky. They named the star TOI-270, for the 270th “TESS Object of Interest” identified to date. The researchers used ground-based instruments to follow up on the star’s activity, and confirmed that the signals are the result of three orbiting exoplanets: planet b, a rocky super-Earth with a roughly three-day orbit; planet c, a sub-Neptune with a five-day orbit; and planet d, another sub-Neptune slightly further out, with an 11-day orbit.</p> <p>Günther notes that the planets seem to line up in what astronomers refer to as a “resonant chain,” meaning that the ratio of their orbits are close to whole integers — in this case, 3:5 for the inner pair, and 2:1 for the outer pair — and that the planets are therefore in “resonance” with each other. Astronomers have discovered other small stars with similarly resonant planetary formations. And in our own solar system, the moons of Jupiter also happen to line up in resonance with each other.</p> <p>“For TOI-270, these planets line up like pearls on a string,” Günther says. “That’s a very interesting thing, because it lets us study their dynamical behavior. And you can almost expect, if there are more planets, the next one would be somewhere further out, at another integer ratio.”</p> <p><strong>“An exceptional laboratory”</strong></p> <p>TOI-270’s discovery initially caused a stir of excitement within the TESS science team, as it seemed, in the first analysis, that planet d might lie in the star’s habitable zone, a region that would be cool enough for the planet’s surface to support water, and possibly life. But the researchers soon realized that the planet’s atmosphere was probably extremely thick, and would therefore generate an intense greenhouse effect, causing the planet’s surface to be too hot to be habitable.</p> <p>But Günther says there is a good possibility that the system hosts other planets, further out from planet d, that might well lie within the habitable zone. Planet d, with an 11-day orbit, is about 10 million kilometers out from the star. Günther says that, given that the star is small and relatively cool — about half as hot as the sun — its habitable zone could potentially begin at around 15 million kilometers. But whether a planet exists within this zone, and whether it is habitable, depends on a host of other parameters, such as its size, mass, and atmospheric conditions.</p> <p>Fortunately, the team writes in their paper that “the host star, TOI-270, is remarkably well-suited for future habitability searches, as it is particularly quiet.” The researchers plan to focus other instruments, including the upcoming James Webb Space Telescope, on TOI-270, to pin down various properties of the three planets, as well as search for additional planets in the star’s habitable zone.</p> <p>“TOI-270 is a true Disneyland for exoplanet science, and one of the prime systems TESS was set out to discover,” Günther says. “It is an exceptional laboratory for not one, but many reasons — it really ticks all the boxes.”</p> <p>This research was funded, in part, by NASA.</p> This infographic illustrates key features of the TOI 270 system, located about 73 light-years away in the southern constellation Pictor. Credit: NASA’s Goddard Space Flight Center/Scott WiessingerTESS, Astronomy, Astrophysics, Kavli Institute, NASA, Planetary science, Research, Satellites, School of Science, space, Space, astronomy and planetary science, Stars Scientists look to synthetic biology and 3-D printing for life support in space Do-it-yourself bio and maker communities can help NASA meet needs of long-distance missions. Fri, 26 Jul 2019 11:45:01 -0400 Kylie Foy | Lincoln Laboratory <p>As NASA gears up to send humans back to the moon or even to Mars, they'll need to figure out how to keep these humans healthy and safe, far away from the resource-abundant Earth.</p> <p>It won't be feasible to pack everything they may need over the course of the mission, and resupply missions like those that keep the International Space Station (ISS) stocked will be prohibitively expensive and lengthy.</p> <p>What these astronauts can pack are Earth's unique renewable resource: cells. Cells of fungi and bacteria, for example, can be reprogrammed with synthetic DNA to produce specific materials, like bioplastics. These materials can then be fed into 3-D printers to manufacture things the astronauts may need during spaceflight — everything from hardware and medical devices to medicine and food.</p> <p>In an opinion piece <a href="">published online</a> in <em>Trends in Biotechnology</em>, researchers from the Universities Space Research Association (USRA), MIT Lincoln Laboratory, and NASA outline ways that synthetic biology and 3-D printing can support life during deep-space human missions. But to make these ideas a reality, NASA is seeking help.</p> <p>"Our opinion piece is a call to action to get DIY [do-it-yourself] biology and makerspace communities involved," says Peter Carr, who works in Lincoln Laboratory's Bioengineering Systems and Technologies Group. The DIY biology community makes it possible for anyone in the public with an interest to conduct biological engineering. The community operates outside the traditional academic or industry settings and spreads knowledge through open sourcing. Many DIY biologist groups operate makerspaces that provide equipment and supplies for members to do experiments on their own.</p> <p>"These separate, eclectic communities do bio in unconventional settings all the time and are pioneers at rapid prototyping and developing technologies with limited resources. There are parallels here with space and the needs of NASA crews," Carr says. "But this also requires organizations like ours and NASA to connect more deeply with them in a two-way process, so there's a real pathway to getting people's work into space. We're just getting started."</p> <p>3-D printers are common staples of makerspaces. Experiments done on the ISS with 3-D printers have proven their utility for manufacturing on-demand items, like replacement hardware. But if 3-D printing is to be a reliable tool for long-duration missions in space, a new problem crops up: the need to supply the ship with the feedstock for the printers.</p> <p>To meet this need, the authors envision using synthetic biology to produce custom biological "ink" to 3-D print whatever may be needed over the course of a mission. Such a process would give scientists "the autonomy to design for the unknown," says Jessica Snyder, a USRA researcher who leads the synthetic biology task for the NASA Academic Mission Services.</p> <p>Living organisms can convert sunlight, nitrogen, and water into finished products. Bioengineers can reprogram the inner logic of these organisms' cells to produce target compounds. The building blocks to edit these cells can be digitized and sent to the space crew in the form of a DNA sequence, which can be synthesized, assembled, and inserted into an organism on ship. "The idea is what we call a 'bits-to-biology' converter," says David Walsh, a bioengineer at Lincoln Laboratory.</p> <p>Here's one example of how this vision could be implemented: Say that astronauts faced a situation that occurred on the ISS in 2007 — a solar panel has torn and needs a repair strap. On Earth, synthetic biologists, whether of the DIY type or not, design and test genetic programs instructing bacteria to produce the polymer feedstock for 3-D printing. (This work could also take place well before the need arises during the space mission.) The maker community works out the design of a strap from those materials. These genetic instructions and 3-D printing instructions are sent digitally from Earth to the space crew. The crew reproduces the genetic program, and the bacteria reproduce and synthesize the raw materials, which are used to 3-D print the strap. At the end of the product's life cycle, the part is recovered and digested, and a new one can be made.&nbsp;</p> <p>"We have the power of digital information. We can design and work out all of the kinks on Earth and simply send the instructions to space," Walsh says.</p> <p>The same principles can be used to insert DNA into organisms in space to make target compounds for food or pharmaceuticals, which if brought directly from Earth would degrade over time from radiation in space.&nbsp;</p> <p>Astronauts would be able to conduct these complex biology experiments by using 3-D-printed microfluidic devices. These tiny "lab-on-a-chip" devices automatically control the flow and mixture of fluids through microchannels and use only trace amounts of chemicals to run hundreds of bioreactions in parallel in seconds. Genetic instructions would be sent directly to electronics controlling these microfluidic devices, enabling them to precisely follow the digital "recipe" to synthetize molecules of DNA.&nbsp;</p> <p>Earlier this year, Lynn Rothschild, a scientist at the NASA Ames Research Center who co-authored the opinion piece, led a team that ran the first synthetic biology experiments in space. The experiments aimed to test how well bacteria in space take in synthetic DNA inserted into their genome and how well the bacteria produce proteins, while being spun to simulate microgravity (what astronauts in the ISS encounter), lunar gravity, and Martian gravity levels. The experiments took place on the PowerCell payload aboard the German satellite mission Eu:CROPIS (Euglena and Combined Regenerative Organic-Food Production in Space).</p> <p>There is still a long way to go, however, both in experimenting with synthetic biology and figuring out all of the parameters that would make 3-D printing with biomaterials possible in space. "For example, bacteria will need water and will take up space; they need the right environment to live; and they'll produce waste. We still need to put these ideas up against the real-world constraints," Carr says.</p> <p>But there's urgency in developing the concepts now. If synthetic biology and 3-D printing techniques can be proven and practiced in time for missions close to Earth, from which supplies can still be sent relatively quickly, then they can be counted on for a long-term mission to Mars.</p> <p>"Flexible manufacturing techniques provide an excellent complement to Earth-based supply chains for destinations days away, like the International Space Station and possible lunar infrastructure, for examples. Let's take advantage of this redundancy to build an in-space manufacturing capacity to take us further into space more safely," Snyder says. Do-it-yourself biologists and makers can help today by publishing their designs for 3-D-printed products, microfluidic devices, or synthetic DNA on open-source repositories and by testing and editing published designs. "If DIY bio communities use, iteratively improve, and ultimately approve of a technique, then that technique has been optimized more robustly than most individuals or team could offer without great effort. Partnering with these communities is an invaluable asset," Snyder adds. People who are interested can also see <a href="">NASA's Centennial Challenges</a>, which outline problems that NASA is seeking the public's help to solve.&nbsp;</p> <p>"We often hear about the engineer who was inspired by NASA in their youth and works there now. But what about the bio people who are inspired by these grand ideas? How can they contribute? Now is a chance to transition their ideas to space," Carr says. "There is so much opportunity to innovate."</p> Microfluidic devices, like those shown here, could be 3-D printed in space and used to construct DNA for insertion into bacteria, reprogramming them to make specific products.Photo: Nicole FandelLincoln Laboratory, NASA, Mars, Space exploration, 3-D printing, Synthetic biology, Bioengineering, Microfluidics, DNA, maker movement Biologists and mathematicians team up to explore tissue folding An algorithm developed to study the structure of galaxies helps explain a key feature of embryonic development. Thu, 25 Jul 2019 11:00:00 -0400 Anne Trafton | MIT News Office <p>As embryos develop, they follow predetermined patterns of tissue folding, so that individuals of the same species end up with nearly identically shaped organs and very similar body shapes.</p> <p>MIT scientists have now discovered a key feature of embryonic tissue that helps explain how this process is carried out so faithfully each time. In a study of fruit flies, they found that the reproducibility of tissue folding is generated by a network of proteins that connect like a fishing net, creating many alternative pathways that tissues can use to fold the right way.</p> <p>“What we found is that there’s a lot of redundancy in the network,” says Adam Martin, an MIT associate professor of biology and the senior author of the study. “The cells are interacting and connecting with each other mechanically, but you don’t see individual cells taking on an all-important role. This means that if one cell gets damaged, other cells can still connect to disparate parts of the tissue.”</p> <p>To uncover these network features, Martin worked with Jörn Dunkel, an MIT associate professor of physical applied mathematics and an author of the paper, to apply an algorithm normally used by astronomers to study the structure of galaxies.</p> <p>Hannah Yevick, an MIT postdoc, is the lead author of the study, which appears today in <em>Developmental Cell</em>. Graduate student Pearson Miller is also an author of the paper.</p> <div class="cms-placeholder-content-video"></div> <p><strong>A safety net</strong></p> <p>During embryonic development, tissues change their shape through a process known as morphogenesis. One important way tissues change shape is to fold, which allows flat sheets of embryonic cells to become tubes and other important shapes for organs and other body parts. Previous studies in fruit flies have shown that even when some of these embryonic cells are damaged, sheets can still fold into their correct shapes.</p> <p>“This is a process that’s fairly reproducible, and so we wanted to know what makes it so robust,” Martin says.</p> <p>In this study, the researchers focused on the process of gastrulation, during which the embryo is reorganized from a single-layered sphere to a more complex structure with multiple layers. This process, and other morphogenetic processes similar to fruit fly tissue folding, also occur in human embryos. The embryonic cells involved in gastrulation contain in their cytoplasm proteins called myosin and actin, which form cables and connect at junctions between cells to form a network across the tissue. Martin and Yevick had hypothesized that the network of cell connectivity might play a role in the robustness of the tissue folding, but until now, there was no good way to trace the connections of the network.</p> <p>To achieve that, Martin’s lab joined forces with Dunkel, who studies the physics of soft surfaces and flowing matter — for example, <a href="">wrinkle formation</a> and <a href="">patterns of bacterial streaming</a>. For this study, Dunkel had the idea to apply a mathematical procedure that can identify topological features of a three-dimensional structure, analogous to ridges and valleys in a landscape. Astronomers use this algorithm to identify galaxies, and in this case, the researchers used it to trace the actomyosin networks across and between the cells in a sheet of tissue.</p> <p>“Once you have the network, you can apply standard methods from network analysis — the same kind of analysis that you would apply to streets or other transport networks, or the blood circulation network, or any other form of network,” Dunkel says.</p> <p>Among other things, this kind of analysis can reveal the structure of the network and how efficiently information flows along it. One important question is how well a network adapts if part of it gets damaged or blocked. The MIT team found that the actomyosin network contains a great deal of redundancy — that is, most of the “nodes” of the network are connected to many other nodes.</p> <p>This built-in redundancy is analogous to a good public transit system, where if one bus or train line goes down, you can still get to your destination. Because cells can generate mechanical tension along many different pathways, they can fold the right way even if many of the cells in the network are damaged.</p> <p>“If you and I are holding a single rope, and then we cut it in the middle, it would come apart. But if you have a net, and cut it in some places, it still stays globally connected and can transmit forces, as long as you don’t cut all of it,” Dunkel says.</p> <p><strong>Folding framework</strong></p> <p>The researchers also found that the connections between cells preferentially organize themselves to run in the same direction as the furrow that forms in the early stages of folding.</p> <p>“We think this is setting up a frame around which the tissue will adopt its shape,” Martin says. “If you prevent the directionality of the connections, then what happens is you can still get folding but it will fold along the wrong axis.”</p> <p>Although this study was done in fruit flies, similar folding occurs in vertebrates (including humans) during the formation of the neural tube, which is the precursor to the brain and spinal cord. Martin now plans to apply the techniques he used in fruit flies to see if the actomyosin network is organized the same way in the neural tube of mice. Defects in the closure of the neural tube can lead to birth defects such as spina bifida.</p> <p>“We would like to understand how it goes wrong,” Martin says. “It’s still not clear whether it’s the sealing up of the tube that’s problematic or whether there are defects in the folding process.”</p> <p>The research was funded by the National Institute of General Medical Sciences and the James S. McDonnell Foundation.</p> At top left are the cell membranes of a normal fruit fly embryo, and at right, overlaid in pink, is the myosin network that connects the cells. At bottom left are the cell membranes of an embryo in which myosin is degraded, and at bottom right, the myosin network is outlined in pink. In both cases, the embryos can still fold normally.Credit: Hannah YevickResearch, Biology, Mathematics, School of Science, Space, astronomy and planetary science New faces in the School of Science faculty Departments of Biology, Brain and Cognitive Sciences, Chemistry, and Physics welcome new faculty members. Tue, 23 Jul 2019 16:00:01 -0400 School of Science <p>This fall, the School of Science will welcome seven new members joining the faculty in the departments of Biology, Brain and Cognitive Sciences, Chemistry, and Physics.</p> <p><a href="">Netta Engelhardt</a> studies gravitational aspects of quantum gravity with an emphasis on string theory She looks into the thermodynamic behavior of black holes and the idea that singularities are always hidden behind event horizons. Engelhardt joins the Department of Physics as an assistant professor. Engelhardt’s BS is in physics and mathematics from Brandeis University, and she received her PhD in physics from the University of California at Santa Barbara. Previously, she was a member of the Princeton Gravity Initiative at Princeton University. Engelhardt is also affiliated with the MIT Center for Theoretical Physics and the Laboratory for Nuclear Science.</p> <p><a href="">Evelina Fedorenko</a> investigates how our brains process language. She has developed novel analytic approaches for functional magnetic resonance imaging (fMRI) and other brain imaging techniques to help answer the questions of how the language processing network functions and how it relates to other networks in the brain. She works with both neurotypical individuals and individuals with brain disorders. Fedorenko joins the Department of Brain and Cognitive Sciences as an assistant professor. She received her BA from Harvard University in linguistics and psychology and then completed her doctoral studies at MIT in 2007. After graduating from MIT, Fedorenko worked as a postdoc and then as a research scientist at the McGovern Institute for Brain Research. In 2014, she joined the faculty at Massachusetts General Hospital and Harvard Medical School, where she was an associate researcher and an assistant professor, respectively. She is also a member of the McGovern Institute.</p> <p><a href="">Erin Kara</a> researches black holes. She looks into their formation and how they grow and impact the environments around them, particularly with respect to event horizons. To do this, she employs X-ray spectral timing observations. Kara is welcomed by the Department of Physics as an assistant professor. Kara joins MIT from the University of Maryland and the NASA Goddard Space flight Center where she was a Hubble Postdoctoral Fellow and a Joint Space-Science Institute Fellow. She received her undergraduate degree from Barnard College in 2011, and an MPhil in astrophysics and PhD in astronomy from Cambridge University. She is also a member of the MIT Kavli Institute for Astrophysics and Space Research.</p> <p><a href="">Pulin Li</a> is a developmental and synthetic biologist. Her work aims to lead to methods that might allow the programming of cells that could produce tissues and cells in regenerative medicine. She and her lab group accomplish this by using bioengineering tools, making quantitative measurements of genetic circuits in natural systems and invoking mathematical modelling. Li is joining the MIT community as an assistant professor in the Department of Biology. Her bachelor’s degree was obtained at Peking University, and she completed a PhD in chemical biology at Harvard University. Prior to her appointment at MIT, she was a postdoc at Caltech. Li is also a member of the Whitehead Institute for Biomedical Research.</p> <p><a href="">Morgan Sheng</a> focuses on the structure, function, and turnover of synapses, the junctions that allow communication between brain cells. His discoveries have improved our understanding of the molecular basis of cognitive function and diseases of the nervous system, such as autism, Alzheimer’s disease, and dementia. Being both a physician and a scientist, he incorporates genetic as well as biological insights to aid the study and treatment of mental illnesses and neurodegenerative diseases. He rejoins the Department of Brain and Cognitive Sciences (BCS), returning as a professor of neuroscience, a position he also held from 2001 to 2008. At that time, he was a member of the Picower Institute for Learning and Memory, a joint appointee in the Department of Biology, and an investigator of the Howard Hughes Medical Institute. Sheng earned his PhD from Harvard University in 1990, completed a postdoc at the University of California at San Francisco in 1994, and finished his medical training with a residency in London in 1986. From 1994 to 2001, he researched molecular and cellular neuroscience at Massachusetts General Hospital and Harvard Medical School. From 2008 to 2019 he was vice president of neuroscience at Genentech, a leading biotech company. In addition to his faculty appointment in BCS, Sheng is core institute member and co-director of the Stanley Center for Psychiatric Research at the Broad Institute of MIT and Harvard, as well as an affiliate member of the McGovern Institute and the Picower Institute.</p> <p><a href="">Seychelle Vos</a> studies genome organization and its effect on gene expression at the intersection of biochemistry and genetics. Vos uses X-ray crystallography, cryo-electron microscopy, and biophysical approaches to understand how transcription is physically coupled to the genome’s organization and structure. She joins the Department of Biology as an assistant professor after completing a postdoc at the Max Plank Institute for Biophysical Chemistry. Vos received her BS in genetics in 2008 from the University of Georgia and her PhD in molecular and cell biology in 2013 from the University of California at Berkeley.</p> <p><a href="">Xiao Wang</a> is a chemist and molecular engineer working to improve our understanding of biology and human health. She focuses on brain function and dysfunction, producing and applying new chemical, biophysical, and genomic tools at the molecular level. Previously, she focused on RNA modifications and how they impact cellular function. Wang is joining MIT as an assistant professor in the Department of Chemistry. She was previously a postdoc of the Life Science Research Foundation at Stanford University. Wang received her BS in chemistry and molecular engineering from Peking University in 2010 and her PhD in chemistry from the University of Chicago in 2015. She is also a core member of the Broad Institute of MIT and Harvard.</p> New faculty of the MIT School of Science: (clockwise from top left) Netta Engelhardt, Evelina Fedorenko, Erin Kara, Pulin Li, Morgan Sheng, Seychelle Vos, and Xiao Wang.Brain and cognitive sciences, School of Science, McGovern Institute, Picower Institute, Biology, Broad Institute, Chemistry, Faculty, Physics, Laboratory for Nuclear Science, Whitehead Institute, Kavli Institute Behind the scenes of the Apollo mission at MIT From making the lunar landings possible to interpreting the meaning of the moon rocks, the Institute was a vital part of history. Thu, 18 Jul 2019 09:23:27 -0400 David L. Chandler | MIT News Office <p>Fifty years ago this week, humanity made its first expedition to another world, when Apollo 11 touched down on the moon and two astronauts walked on its surface. That moment changed the world in ways that still reverberate today.</p> <p>MIT’s deep and varied connections to that epochal event — <a href="">many</a> of <a href="">which</a> have been <a href="">described</a> on <em>MIT News</em> — began years before the actual landing, when the MIT Instrumentation Laboratory (now Draper) signed the very first contract to be awarded for the Apollo program after its announcement by President John F. Kennedy in 1961. The Institute’s involvement continued throughout the program — and is still ongoing today.</p> <p>MIT’s role in creating the navigation and guidance system that got the mission to the moon and back has been widely recognized in books, movies, and television series. But many other aspects of the Institute’s involvement in the Apollo program and its legacy, including advances in mechanical and computational engineering, simulation technology, biomedical studies, and the geophysics of planet formation, have remained less celebrated.</p> <p>Amid the growing chorus of recollections in various media that have been appearing around this 50th anniversary, here is a small collection of bits and pieces about some of the unsung heroes and lesser-known facts from the Apollo program and MIT’s central role in it.</p> <p><strong>A new age in electronics</strong></p> <p>The computer system and its software that controlled the spacecraft — called the Apollo Guidance Computer and designed by the MIT Instrumentation Lab team under the leadership of Eldon Hall — were remarkable achievements that helped push technology forward in many ways.</p> <p>The AGC’s programs were written in one of the first-ever compiler languages, called MAC, which was developed by Instrumentation Lab engineer <a href="" target="_blank">Hal Laning</a>. The computer itself, the 1-cubic-foot Apollo Guidance Computer, was the first significant use of silicon integrated circuit chips and greatly accelerated the development of the microchip technology that has gone on to change virtually every consumer product.</p> <p>In an age when most computers took up entire climate-controlled rooms, the compact AGC was uniquely small and lightweight. But most of its “software” was actually hard-wired: The programs were woven, with tiny donut-shaped metal “cores” strung like beads along a set of wires, with a given wire passing outside the donut to represent a zero, or through the hole for a 1. These so-called rope memories were made in the Boston suburbs at Raytheon, mostly by women who had been hired because they had experience in the weaving industry. Once made, there was no way to change individual bits within the rope, so any change to the software required weaving a whole new rope, and last-minute changes were impossible.</p> <p>As David Mindell, the <em>Frances and David Dibner Professor of the History of Engineering and Manufacturing,</em> points out in his book “Digital Apollo,” that system represented the first time a computer of any kind had been used to control, in real-time, many functions of a vehicle carrying human beings — a trend that continues to accelerate as the world moves toward self-driving vehicles. Right after the Apollo successes, the AGC was directly adapted to an F-8 fighter jet, to create the first-ever fly-by-wire system for aircraft, where the plane’s control surfaces are moved via a computer rather than direct cables and hydraulic systems. This approach is now widespread in the aerospace industry, says John Tylko, who teaches MIT’s class <a href="" target="_blank">16.895J</a> (Engineering Apollo: The Moon Project as a Complex System), which is taught every other year.</p> <p>As sophisticated as the computer was for its time, computer users today would barely recognize it as such. Its keyboard and display screen looked more like those on a microwave oven than a computer: a simple numeric keypad and a few lines of five-digit luminous displays. Even the big mainframe computer used to test the code as it was being developed had no keyboard or monitor that the programmers ever saw. Programmers wrote their code by hand, then typed it onto punch cards — one card per line — and handed the deck of cards to a computer operator. The next day, the cards would be returned with a printout of the program’s output. And in this time long before email, communications among the team often relied on handwritten paper notes.</p> <p><strong>Priceless rocks</strong></p> <p>MIT’s involvement in the geophysical side of the Apollo program also extends back to the early planning stages — and continues today. For example, Professor Nafi Toksöz, an expert in seismology, helped to develop a seismic monitoring station that the astronauts placed on the moon, where it helped lead to a greater understanding of the moon’s structure and formation. “It was the hardest work I have ever done, but definitely the most exciting,” <a href="">he has said</a>.</p> <p>Toksöz says that the data from the Apollo seismometers “changed our understanding of the moon completely.” The seismic waves, which on Earth continue for a few minutes, lasted for two hours, which turned out to be the result of the moon’s extreme lack of water. “That was something we never expected, and had never seen,” he recalls.</p> <p>The first seismometer was placed on the moon’s surface very shortly after the astronauts landed, and seismologists including Toksöz started seeing the data right away — including every footstep the astronauts took on the surface. Even when the astronauts returned to the lander to sleep before the morning takeoff, the team could see that Buzz Aldrin&nbsp;ScD ’63 and Neil Armstrong were having a sleepless night, with every toss and turn dutifully recorded on the seismic traces.</p> <p>MIT Professor Gene Simmons was among the first group of scientists to gain access to the lunar samples as soon as NASA released them from quarantine, and he and others in what is now the Department of Earth, Planetary and Atmospheric Sciences (EAPS) have continued to work on these samples ever since. As part of a conference on campus, he exhibited some samples of lunar rock and soil in their first close-up display to the public, where some people may even have had a chance to touch the samples.</p> <p>Others in EAPS have also been studying those Apollo samples almost from the beginning. Timothy Grove, the Robert R. Shrock Professor of Earth and Planetary Sciences, started studying the Apollo samples in 1971 as a graduate student at Harvard University, and has been doing research on them ever since. Grove says that these samples have led to major new understandings of planetary formation processes that have helped us understand the Earth and other planets better as well.</p> <p>Among other findings, the rocks showed that ratios of the isotopes of oxygen and other elements in the moon rocks were identical to those in terrestrial rocks but completely different than those of any meteorites, proving that the Earth and the moon had a common origin and leading to the hypothesis that the moon was created through a giant impact from a planet-sized body. The rocks also showed that the entire surface of the moon had likely been molten at one time. The idea that a planetary body could be covered by an ocean of magma was a major surprise to geologists, Grove says.</p> <p>Many puzzles remain to this day, and the analysis of the rock and soil samples goes on. “There’s still a lot of exciting stuff” being found in these samples, Grove says.</p> <p><strong>Sorting out the facts</strong></p> <p>In the spate of publicity and new books, articles, and programs about Apollo, inevitably some of the facts — some trivial, some substantive — have been scrambled along the way. “There are some myths being advanced,” says Tylko, some of which he addresses in his “Engineering Apollo” class. “People tend to oversimplify” many aspects of the mission, he says.</p> <p>For example, many accounts have described the sequence of alarms that came from the guidance computer during the last four minutes of the mission, forcing mission controllers to make the daring decision to go ahead despite the unknown nature of the problem. But Don Eyles, one of the Instrumentation Lab’s programmers who had written the landing software for the AGC, says that he can’t think of a single account he’s read about that sequence of events that gets it entirely right. According to Eyles, many have claimed the problem was caused by the fact that the rendezvous radar switch had been left on, so that its data were overloading the computer and causing it to reboot.</p> <p>But Eyles says the actual reason was a much more complex sequence of events, including a crucial mismatch between two circuits that would only occur in rare circumstances and thus would have been hard to detect in testing, and a probably last-minute decion to put a vital switch in a position that allowed it to happen. Eyles has described these details in a memoir about the Apollo years and in a technical paper <a href="" target="_blank">available online</a>, but he says they are difficult to summarize simply. But he thinks the author Norman Mailer may have come closest, capturing the essence of it in his book “Of a Fire on the Moon,” where he describes the issue as caused by a “sneak circuit” and an “undetectable” error in the onboard checklist.</p> <p>Some accounts have described the AGC as a very limited and primitive computer compared to today’s average smartphone, and Tylko acknowledges that it had a tiny fraction of the power of today’s smart devices — but, he says, “that doesn’t mean they were unsophisticated.” While the AGC only had about 36 kilobytes of read-only memory and 2 kilobytes of random-access memory, “it was exceptionally sophisticated and made the best use of the resources available at the time,” he says.</p> <p>In some ways it was even ahead of its time, Tylko says. For example, the compiler language developed by Laning along with Ramon Alonso at the Instrumentation Lab used an architecture that he says was relatively intuitive and easy to interact with. Based on a system of “verbs” (actions to be performed) and “nouns” (data to be worked on), “it could probably have made its way into the architecture of PCs,” he says. “It’s an elegant interface based on the way humans think.”</p> <p>Some accounts go so far as to claim that the computer failed during the descent and astronaut Neil Armstrong had to take over the controls and land manually, but in fact partial manual control was always part of the plan, and the computer remained in ultimate control throughout the mission. None of the onboard computers ever malfunctioned through the entire Apollo program, according to astronaut David Scott SM ’62, who used the computer on two Apollo missions: “We never had a failure, and I think that is a remarkable achievement.”</p> <p><strong>Behind the scenes</strong></p> <p>At the peak of the program, a total of about 1,700 people at MIT’s Instrumentation Lab were working on the Apollo program’s software and hardware, according to Draper, the Instrumentation Lab’s successor, which spun off from MIT in 1973. A few of those, such as the near-legendary <a href="">“Doc” Draper</a> himself — Charles Stark Draper ’26, SM ’28, ScD ’38, former head of the Department of Aeronautics and Astronautics (AeroAstro) — have become widely known for their roles in the mission, but most did their work in near-anonymity, and many went on to entirely different kinds of work after the Apollo program’s end.</p> <p><a href="">Margaret Hamilton</a>, who directed the Instrumentation Lab’s Software Engineering Division, was little known outside of the program itself until an <a href="" target="_self">iconic photo</a> of her next to the original stacks of AGC code began making the rounds on social media in the mid 2010s. In 2016, when she was awarded the Presidential Medal of Freedom by President Barack Obama, MIT Professor Jaime Peraire, then head of AeroAstro, said of Hamilton that “She was a true software engineering pioneer, and it’s not hyperbole to say that she, and the Instrumentation Lab’s Software Engineering Division that she led, put us on the moon.” After Apollo, Hamilton went on to found a software services company, which she still leads.</p> <p>Many others who played major roles in that software and hardware development have also had their roles little recognized over the years. For example, Hal Laning ’40, PhD ’47, who developed the programming language for the AGC, also devised its executive operating system, which employed what was at the time a new way of handling multiple programs at once, by assigning each one a priority level so that the most important tasks, such as controlling the lunar module’s thrusters, would always be taken care of. “Hal was the most brilliant person we ever had the chance to work with,” Instrumentation Lab engineer Dan Lickly <em><a href="" target="_blank">told MIT Technology Review</a></em>. And that priority-driven operating system proved crucial in allowing the Apollo 11 landing to proceed safely in spite of the 1202 alarms going off during the lunar descent.</p> <p>While the majority of the team working on the project was male, software engineer Dana Densmore recalls that compared to the heavily male-dominated workforce at NASA at the time, the MIT lab was relatively welcoming to women. Densmore, who was a control supervisor for the lunar landing software, told <em>The Wall Street Journal</em> that “NASA had a few women, and they kept them hidden. At the lab it was very different,” and there were opportunities for women there to take on significant roles in the project.</p> <p>Hamilton recalls the atmosphere at the Instrumentation Lab in those days as one of real dedication and meritocracy. As she told <a href="">MIT News in 2009</a>, “Coming up with solutions and new ideas was an adventure. Dedication and commitment were a given. Mutual respect was across the board. Because software was a mystery, a black box, upper management gave us total freedom and trust. We had to find a way and we did. Looking back, we were the luckiest people in the world; there was no choice but to be pioneers.”</p> The computer system and software that controlled the Apollo 11 spacecraft — called the Apollo Guidance Computer and designed by the MIT Instrumentation Lab team — helped push technology forward in many ways. The computer itself was the first significant use of silicon integrated circuit chips.Image courtesy of the MIT MuseumAeronautical and astronautical engineering, EAPS, Research, Satellites, School of Engineering, History of MIT, NASA, History of science, Moon, Space, astronomy and planetary science, Women in STEM, School of Science Breaching a “carbon threshold” could lead to mass extinction Carbon dioxide emissions may trigger a reflex in the carbon cycle, with devastating consequences, study finds. Mon, 08 Jul 2019 14:59:59 -0400 Jennifer Chu | MIT News Office <p>In the brain, when neurons fire off electrical signals to their neighbors, this happens through an “all-or-none” response. The signal only happens once conditions in the cell breach a certain threshold.</p> <p>Now an MIT researcher has observed a similar phenomenon in a completely different system: Earth’s carbon cycle.</p> <p>Daniel Rothman, professor of geophysics and co-director of the Lorenz Center in MIT’s Department of Earth, Atmospheric and Planetary Sciences, has found that when the rate at which carbon dioxide enters the oceans pushes past a certain threshold — whether as the result of a sudden burst or a slow, steady influx — the Earth may respond with a runaway cascade of chemical feedbacks, leading to extreme ocean acidification that dramatically amplifies the effects of the original trigger.</p> <p>This global reflex causes huge changes in the amount of carbon contained in the Earth’s oceans, and geologists can see evidence of these changes in layers of sediments preserved over hundreds of millions of years.</p> <p>Rothman looked through these geologic records and observed that over the last 540 million years, the ocean’s store of carbon changed abruptly, then recovered, dozens of times in a fashion similar to the abrupt nature of a neuron spike. This “excitation” of the carbon cycle occurred most dramatically near the time of four of the five great mass extinctions in Earth’s history.</p> <p>Scientists have attributed various triggers to these events, and they have assumed that the changes in ocean carbon that followed were proportional to the initial trigger — for instance, the smaller the trigger, the smaller the environmental fallout.</p> <p>But Rothman says that’s not the case. It didn’t matter what initially caused the events; for roughly half the disruptions in his database, once they were set in motion, the rate at which carbon increased was essentially the same.&nbsp; Their characteristic rate is likely a property of the carbon cycle itself — not the triggers, because different triggers would operate at different rates.</p> <p>What does this all have to do with our modern-day climate? Today’s oceans are absorbing carbon about an order of magnitude faster than the worst case in the geologic record — the end-Permian extinction. But humans have only been pumping carbon dioxide into the atmosphere for hundreds of years, versus the tens of thousands of years or more that it took for volcanic eruptions or other disturbances to trigger the great environmental disruptions of the past. Might the modern increase of carbon be too brief to excite a major disruption?</p> <p>According to Rothman, today we are “at the precipice of excitation,” and if it occurs, the resulting spike — as evidenced through ocean acidification, species die-offs, and more — is likely to be similar to past global catastrophes.</p> <p>“Once we’re over the threshold, how we got there may not matter,” says Rothman, who is publishing his results this week in the <em>Proceedings of the National Academy of Sciences.</em> “Once you get over it, you’re dealing with how the Earth works, and it goes on its own ride.”</p> <p><strong>A carbon feedback</strong></p> <p>In 2017, Rothman made <a href="">a dire prediction</a>: By the end of this century, the planet is likely to reach a critical threshold, based on the rapid rate at which humans are adding carbon dioxide to the atmosphere. When we cross that threshold, we are likely to set in motion a freight train of consequences, potentially culminating in the Earth’s sixth mass extinction.</p> <p>Rothman has since sought to better understand this prediction, and more generally, the way in which the carbon cycle responds once it’s pushed past a critical threshold. In the new paper, he has developed a simple mathematical model to represent the carbon cycle in the Earth’s upper ocean and how it might behave when this threshold is crossed.</p> <p>Scientists know that when carbon dioxide from the atmosphere dissolves in seawater, it not only makes the oceans more acidic, but it also decreases the concentration of carbonate ions. When the carbonate ion concentration falls below a threshold, shells made of calcium carbonate dissolve. Organisms that make them fare poorly in such harsh conditions.</p> <p>Shells, in addition to protecting marine life, provide a “ballast effect,” weighing organisms down and enabling them to sink to the ocean floor along with detrital organic carbon, effectively removing carbon dioxide from the upper ocean. But in a world of increasing carbon dioxide, fewer calcifying organisms should mean less carbon dioxide is removed.</p> <p>“It’s a positive feedback,” Rothman says. “More carbon dioxide leads to more carbon dioxide. The question from a mathematical point of view is, is such a feedback enough to render the system unstable?”</p> <p><strong>“</strong><strong>An inexorable rise</strong><strong>”</strong></p> <p>Rothman captured this positive feedback in his new model, which comprises two differential equations that describe interactions between the various chemical constituents in the upper ocean. He then observed how the model responded as he pumped additional carbon dioxide into the system, at different rates and amounts.</p> <p>He found that no matter the rate at which he added carbon dioxide to an already stable system, the carbon cycle in the upper ocean remained stable. In response to modest perturbations, the carbon cycle would go temporarily out of whack and experience a brief period of mild ocean acidification, but it would always return to its original state rather than oscillating into a new equilibrium.</p> <p>When he introduced carbon dioxide at greater rates, he found that once the levels crossed a critical threshold, the carbon cycle reacted with a cascade of positive feedbacks that magnified the original trigger, causing the entire system to spike, in the form of severe ocean acidification. The system did, eventually, return to equilibrium, after tens of thousands of years in today’s oceans — an indication that, despite a violent reaction, the carbon cycle will resume its steady state.</p> <p>This pattern matches the geological record, Rothman found. The characteristic rate exhibited by half his database results from excitations above, but near, the threshold. Environmental disruptions associated with mass extinction are outliers — they represent excitations well beyond the threshold. At least three of those cases may be related to sustained massive volcanism.</p> <p>“When you go past a threshold, you get a free kick from the system responding by itself,” Rothman explains. “The system is on an inexorable rise. This is what excitability is, and how a neuron works too.”</p> <p>Although carbon is entering the oceans today at an unprecedented rate, it is doing so over a geologically brief time. Rothman’s model predicts that the two effects cancel: Faster rates bring us closer to the threshold, but shorter durations move us away. Insofar as the threshold is concerned, the modern world is in roughly the same place it was during longer periods of massive volcanism.&nbsp;</p> <p>In other words, if today’s human-induced emissions cross the threshold and continue beyond it, as Rothman predicts they soon will, the consequences may be just as severe as what the Earth experienced during its previous mass extinctions.</p> <p>“It’s difficult to know how things will end up given what’s happening today,” Rothman says. “But we’re probably close to a critical threshold. Any spike would reach its maximum after about 10,000 years. Hopefully that would give us time to find a solution.”</p> <p>“We already know that our CO<sub>2</sub>-emitting actions will have consequences for many millennia,” says Timothy Lenton, professor of climate change and earth systems science at the University of Exeter. “This study suggests those consequences could be much more dramatic than previously expected. If we push the Earth system too far, then it takes over and determines its own response — past that point there will be little we can do about it.”</p> <p>This research was supported, in part, by NASA and the National Science Foundation.</p> When carbon emissions pass a critical threshold, it can trigger a spike-like reflex in the carbon cycle, in the form of severe ocean acidification that lasts for 10,000 years, according to a new MIT study.Stock imageCarbon, Climate, Climate change, EAPS, Earth and atmospheric science, Emissions, Environment, Geology, Global Warming, Greenhouse gases, Mathematics, Research, School of Science, NASA, National Science Foundation (NSF) 3Q: Julien de Wit on searching for red worlds in the northern skies MIT has completed the installation of its newest exoplanet-hunting telescope, Artemis, in the Canary Islands, joining the SPECULOOS network. Thu, 20 Jun 2019 09:00:00 -0400 Lauren Hinkel | EAPS <p><em>With a new telescope situated on a scenic plateau in Tenerife, Spain, MIT planetary scientists now have an added way to search for Earth-sized exoplanets. Artemis, the first ground-based telescope of the SPECULOOS Northern Observatory (SNO), joins a network of 1-meter-class robotic telescopes as part of the <a href="" target="_blank">SPECULOOS</a> project (Search for habitable Planets EClipsing ULtra-cOOl Stars), which is led by Michael Gillon at the University of Liège in Belgium and carried out </em><em>in collaboration with <a href="" target="_blank">MIT and several other institutions and financial supporters</a>. Artemis is the latest product of a collaboration with MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). The other network telescopes that make up the SPECULOOS Southern Observatory — named Io, Europa, Ganymede, and Callisto after the four Galilean moons of Jupiter — are up and running at the Paranal Observatory in Chile, busily scanning the skies for exoplanets in the Southern Hemisphere. </em></p> <p><em>Together, these SPECULOOS telescopes will look for terrestrial planets circling very faint, nearby stars, called ultra-cool dwarfs, and the new Artemis telescope will allow the research group to expand the search into the Northern Hemisphere skies. Artemis was unveiled today at an inauguration event attended by scientists and dignitaries from MIT, the University of Liège, and the <a href=";hl=en&amp;prev=search&amp;;sl=es&amp;sp=nmt4&amp;u=;xid=17259,15700023,15700186,15700190,15700256,15700259&amp;usg=ALkJrhgjrtmDa-A1G9IirbelQMAIh33RVQ">Instituto de Astrofísica de Canarias</a> (IAC) in Tenerife. Artemis was funded by MIT donors Peter A. Gilman, the Heising-Simons Foundation, and Colin and Leslie Masson, with additional support from the Ministry of Higher Education of the Federation Wallonie-Bruxelles, and the Balzan Foundation.</em></p> <div class="cms-placeholder-content-video"></div> <p><em>Before the SPECULOOS telescopes were conceived, researchers had already established the proof of concept for this technique with a project using a small, ground-based telescope located in La Silla, Chile, known as TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope). With the TRAPPIST telescope, researchers looked at a limited sample of 50 target stars and discovered the TRAPPIST-1 system, which consists of seven terrestrial planets orbiting their cool, ultra-dwarf star. To date, these are the only known planets that are nearby, Earth-sized, temperate, and amenable for future atmospheric characterization, setting them apart from previous exoplanet findings. The SPECULOOS group is building on this earlier project with its new telescope network to scan more of the sky for similar Earth-sized exoplanets, and deliver more targets that can be assessed for habitability and potentially signs of life in the future.</em></p> <p><em>Julien de Wit is an EAPS assistant professor, SPECULOOS collaborator, Artemis principal investigator, and SNO co-principal investigator with Gillon. As a postdoc in the group of MIT Professor Sara Seager, he worked with Gillon and the TRAPPIST team to identify and characterize the TRAPPIST-1 system. Later he spearheaded the expansion of the SPECULOOS venture into the Northern Hemisphere. EAPS recently spoke with de Wit about the capabilities of Artemis and what we can expect to find with the SPECULOOS project.</em></p> <p><strong>Q: </strong>Tell us about the new Artemis telescope. Why is it particularly exciting?</p> <p><strong>A:</strong> The first telescope of the SPECULOOS Northern Observatory is named Artemis, built and owned by MIT, after the Greek goddess of the hunt, the wilderness, the moon, which seemed appropriate as we are hunting for planets and signs of life.</p> <p>Artemis is located on the Spanish Canary Island of Tenerife about 150 miles off the coast of Morocco. The SNO is built within the Teide Observatory, which is an astronomical observatory by the Teide Volcano, 2,400 meters above sea level and operated by the Insituto de Astrofisica de Canarias. The location, which hosts one of the first major international observatories, boasts excellent astronomical conditions for viewing.</p> <p>As far as the telescope itself, it measures about 4 meters high, with an optical quality of less than 0.8 arcsec and a field of view, 12 arcmin by 12 arcmin. Artemis, which was built by the German company ASTELCO, has a robot mount, and its detectors are very sensitive to the near-infrared wavelengths that we find emanating from these ultra-cool dwarf stars. We will be operating it remotely from MIT or any other collaborating institutes.</p> <p>With TRAPPIST, we demonstrated a proof of concept — confirming that ultra-cool dwarf stars have the capacity to host planets — and are investigating the atmospheres of these TRAPPIST-1 planets with the Hubble Space Telescope. To date, there are no other temperate Earth-sized planets that would be such exquisite targets for atmospheric study. This justified fully scaling up with the SPECULOOS project.</p> <p>Telescopes like this provide two important observational advantages. One, due to similar planet-to-star area ratios, the signal we’ll get from an Earth-sized planet transiting an ultra-cool dwarf star will be similar to a Jupiter-sized planet crossing in front of a sun-like star. Two, the vicinity of their habitable zone, due to their small size and temperature, means that habitable planets will have small transit periodicities, similar to gas giants, which are in close orbit around solar-type stars. This means that each star will require less monitoring time, and that the transit search targeting the roughly 1,200 nearest ultra-cool stars could be done in about 10 years with four telescopes scanning each hemisphere.</p> <p><strong>Q: </strong>What is the goal of Artemis, and how many exoplanets do you estimate can be evaluated by MIT’s new SPECULOOS Northern Observatory?</p> <p><strong>A:</strong> Over each night, we will be gathering pictures of a specific section of the sky, focused on our target stars in order to search for a brightness drop characteristic of a planetary transit.</p> <p>The goal of the Artemis telescope is to look at the roughly 800 nearest ultra-cool dwarf stars located in the northern skies (and a sliver of the southern skies) to find Earth-sized planets that may have a temperate climate and be amenable for further in-depth characterization with the next generation of observatories, such as the James Webb Space Telescope (JWST) and the Extremely Large Telescopes. These will be able to tell us more about their atmosphere, climate, and what molecules might be present on them. We are confidently expecting to identify about 15 temperate planets with the SPECULOOS network, and doing so on a relevant timeline, which will allow for their atmospheres to be studied with the JWST, which is expected to launch in 2021 and last for 10 years.</p> <p>Additionally, we’ll expand Artemis’s scope of work. We plan to do a follow-up of some of the trickiest planet candidates (terrestrial planets around small M-dwarfs) identified by the MIT-led TESS [Transiting Exoplanet Survey Satellite] NASA mission, since Artemis has 100 times larger viewing areas. We’ll also be able to study asteroids, comets, and other objects, such as observations of the Quaoar occultation, with other scientists at MIT and outside of the Institute.</p> <p><strong>Q: </strong>You mentioned that Artemis is the first telescope for the SPECULOOS Northern Observatory. Does that mean more telescopes might be added to the SPECULOOS network in the future?</p> <p><strong>A:</strong> Yes, we hope to build out the SPECULOOS Northern Observatory and add telescopes to accompany Artemis. As a matter of fact, we have already built an additional platform ready to host a twin to Artemis, as soon as we have found additional funding. Our agreement with the Teide Observatory reserves space to accommodate up to three additional telescopes. Doing so will allow us to thoroughly study all the nearest ultra-cool dwarf stars and complete the Northern Hemisphere survey in time to perform the atmospheric characterization of their transiting planets with the JWST.</p> <p>With SPECULOOS, we are giving it our best shot at enabling the identification of habitats beyond Earth within the next decade. Our team is looking forward to sharing “first light” with our donors and the public, and it is a privilege for MIT to be working with our international partners on this exciting venture.</p> Artemis searches the Northern Hemisphere sky for exoplanets.Photo: D. PadronEAPS, School of Science, Astronomy, Planetary science, Exoplanets, TESS, Space, astronomy and planetary science, 3 Questions, Physics, Astrophysics, Sensors Four 2019 40 Under 40 award winners are from Lincoln Laboratory The Armed Forces Communications and Electronics Association recognizes innovation and leadership in science and technology. Wed, 19 Jun 2019 11:00:01 -0400 Lucas Principe | Lincoln Laboratory <p>Each year, the Armed Forces Communications and Electronics Association (AFCEA) presents the Young AFCEA 40 Under 40 award to 40 individuals under age 40 for their significant contributions to science, technology, engineering, and mathematics (STEM). This year, the Lincoln Laboratory is home to four winners: Anu Myne, Mark Veillette, Meredith Drennan, and Alexander Stolyarov. The recipients are chosen by AFCEA for the innovation, leadership, and support they provide to their organizations, particularly through the application of information technology to make advancements in STEM.</p> <p><strong>Anu Myne</strong></p> <p>Myne currently serves as an associate technology officer within the Lincoln Laboratory Technology Office, where she supports the strategic development of the laboratory’s internal investments and innovation initiatives, and furthers collaboration with MIT campus. In this role, she’s focusing on the laboratory’s overall strategies for advancing research and development in artificial intelligence (AI) for national security. Among various other projects, Myne organized the AI Technical Interchange meeting for laboratory-wide participation last year, and is now planning the inaugural Recent Advances in AI for National Security Workshop that will be held in 2019.</p> <p>"It has been a distinct privilege to work with Anu, one of our rising stars at the laboratory," says Robert Bond, chief technology officer. "Anu has an impressively diverse professional resume spanning hardware design, signal processing, and machine learning. This background, coupled with her natural inquisitiveness and ability to zero in on the important technology issues, has made her ideal for her current role as associate technology officer."</p> <p>Before joining the Technology Office, Myne made significant contributions to a diverse set of problems addressing challenges in electronic warfare and radar systems for next-generation defense. Her efforts ranged from system analysis and development of simulation tools to hardware design, implementation, and testing.</p> <p>Myne believes that every opportunity she's had to develop, test, and demonstrate system concepts was a great experience. She’s been most recognized for her efforts in developing a novel electromagnetic environment simulation tool and a Bayesian network approach for intelligent test design — successes she attributes to an appreciation for both real hardware and software design challenges and her willingness to try out new ideas or approaches.</p> <p>Upon winning the award, Myne said, "The laboratory is filled with talent and I'm honored to be recognized this way."</p> <p><strong>Mark Veillette</strong></p> <p>Veillette began working in the Air Traffic Control Systems Group in 2010. Since then, his main focus has been the application of AI and machine learning in weather sensing and forecasting. "As you can imagine, weather involves a lot of data and uncertainty, so I think it's a very rich and exciting space to be applying these types of algorithms," Veillette says.</p> <p>Currently, Veillette is working on a project to create a global picture of synthetic weather radar. The data used for the project are similar to weather radar imagery seen on the news, except that these data will be available globally, even in areas without weather radar.</p> <p>"Mark is not only an expert in his field, he is a consummate teacher," colleague Christopher Mattioli says. "Even at his most busy and stressful times, he's always willing to offer technical guidance and listen to new ideas. His type of character fosters a healthy working environment, which ultimately strengthens and expedites innovation."</p> <p>Veillette says he is particularly proud of organizing and teaching a technical education course titled Decision Making Under Uncertainty. He has also been involved in various support roles across groups and divisions, and has served on the Laboratory's Advanced Concepts Committee for the past two and a half years.</p> <p>"There are so many talented people here at the laboratory and at other institutions supporting the Department of Defense, so to be recognized by the AFCEA is very nice," Veillette says. "I’m thankful to the Director’s Office for nominating me."</p> <p><strong>Meredith Drennan</strong></p> <p>Drennan has been working at the laboratory since 2010, when she started as an associate staff member in the Integrated Systems and Concepts Group. Since that time, she has worked on an assortment of laboratory projects and is now an assistant leader of her group.</p> <p>From 2010-14, as part of the Multi-Aperture Sparse Imager Video System and Wide-Area Infrared System for Persistent Surveillance teams, she developed software for wide-area motion imagery processing.</p> <p>Since 2014, Drennan has been the lead flight software developer for the SensorSat program — a project to build a next-generation surveillance satellite. She was made program manager of this project in 2018.</p> <p>What Drennan appreciates most about her work at the laboratory has been the opportunity to contribute technically while working with great people on difficult problems. She pointed to her work on SensorSat as the reason for her receiving this award: "While I admit I worked very hard on that program, I was one of many. Any successes the satellite has had are a result of the hard work and dedication of dozens of individuals, not just one."</p> <p><strong>Alexander (Sasha) Stolyarov</strong></p> <p>Stolyarov, a staff member in the Chemical, Microsystem, and Nanoscale Technologies Group, currently leads the Defense Fabric Discovery Center (DFDC) — an end-to-end advanced fabrics prototyping facility focused on developing multifunctional fibers and fabrics for national security. The DFDC, opened in October 2017, is one of a planned network of fabric discovery centers and was built in a joint venture among the laboratory, the Commonwealth of Massachusetts, the Advanced Functional Fabrics of America, and the Combat Capabilities Development Command Soldier Center (formerly called the U.S. Army Natick Soldier Research, Development and Engineering Center).</p> <p>Shortly after joining the laboratory in 2014, Stolyarov began working on a program involving multimaterial fiber devices. The program seeks to incorporate these devices into fabrics for a variety of uses, including fabric-based chemical sensors and optical communication systems.</p> <p>Stolyarov says that his greatest accomplishment at the laboratory has been "starting and growing the advanced fibers technical area, which has grown from a group project to an enterprise involving collaborations with many of the laboratory’s system divisions."</p> <p>Livia Racz, associate leader of the Chemical, Microsystem, and Nanoscale Technologies Group, says, "Sasha had a passion for this subject since he first started at the laboratory. When we first saw his proposal, we realized that it promised to become a perfect example of what we were looking for — a rapid, scalable way to break the paradigm of electronics on flat circuit boards."</p> The 2019 Young AFCEA 40 Under 40 award winners from Lincoln Laboratory are (left to right): Anu Myne, Mark Veillette, Meredith Drennan, and Alexander Stolyarov.Photo: Nicole FandelLincoln Laboratory, Awards, honors and fellowships, Radar, Aviation, Space, astronomy and planetary science, Earth and atmospheric sciences How to detect life on Mars Scientists from the Search for Extra-Terrestrial Genomes instrument team develop method to detect the tiniest traces of life on other planetary bodies. Mon, 17 Jun 2019 09:00:00 -0400 Fatima Husain | EAPS <p>When MIT research scientist Christopher Carr visited a green sand beach in Hawaii at the age of 9, he probably didn’t think that he’d use the little olivine crystals beneath his feet to one day search for extraterrestrial life. Carr, now the science principal investigator for the Search for Extraterrestrial Genomes (SETG) instrument being developed jointly by the Department of Earth, Atmospheric and Planetary Sciences (EAPS) at MIT and Massachusetts General Hospital, works to wed the worlds of biology, geology, and planetary science to help understand how life evolved in the universe.</p> <p>“Our history revealed by science is a truly incredible story,” Carr says. “You and I are a part of an unbroken chain of 4 billion years of evolution. I want to know more about that story.” &nbsp;</p> <p>SETG was initially proposed by professor of genetics at Harvard Medical School Gary Ruvkun, and since 2005 has been led by Maria Zuber, the E. A. Griswold Professor of Geophysics in EAPS and vice president for research at MIT.</p> <p>As the science principle investigator of SETG, Carr, along with a large team of scientists and engineers, has helped develop instrumentation that could withstand radiation and detect DNA, a type of nucleic acid that carries genetic information in most living organisms, in spaceflight environments. Now, Carr and his colleagues are working to fine-tune the instrumentation to work on the red planet. To do that, the team needed to simulate the kinds of soils thought to preserve evidence of life on Mars, and for that, they needed a geologist.</p> <p>Angel Mojarro, a graduate student in EAPS, was up for the task. Mojarro spent months synthesizing Martian soils that represented different regions on Mars, as established by Martian rover data.</p> <p>“Turns out you can buy most of the rocks and minerals found on Mars online,” Mojarro says. But not all.</p> <p>One of the hard-to-find components of the soils was olivine from the beach Carr had visited as a child: “I called up my folks and said, ‘Hey, can you find the olivine sand in the basement and send me some of that?’”</p> <p>After creating a collection of different Mars analog soils, Mojarro wanted to find out whether SETG could extract and detect small amounts of DNA embedded in those soils as it would do on a future Mars mission. While many technologies already exist on Earth to detect and sequence DNA, scaling down the instrumentation to fit on a rover, survive transport from Earth, and conduct high fidelity sequencing in a harsh Martian environment is a unique challenge. “That’s a whole bunch of steps, no matter what the sequencing technology is right now,” Carr says.</p> <p>The SETG instrumentation has evolved and improved since its development began in 2005, and, currently, the team is working to integrate a new method, called nanopore sequencing, into their work. “In nanopore sequencing, DNA strands travel through nano-sized holes, and the sequence of bases are detected via changes in an ionic current,” Mojarro says.</p> <p>By themselves, Mojarro’s Mars analog soils didn’t contain microbes, so to test and develop nanopore sequencing of DNA in Mars analog soils, Mojarro added known quantities of spores from the bacterium <em>Bacillus subtilis</em> to the soils. Without human help on Mars, SETG instrumentation would need to be able to collect, purify, and enable the DNA to be sequenced, a process which usually necessitates about a microgram of DNA on Earth, Mojarro says.</p> <p>The group’s results using the new sequencing and preparation method, which were reported in <em>Astrobiology</em>, pushed the limits of detection to the parts-per-billion scale — which means even the tiniest traces of life could be detected and sequenced by the instrument.</p> <p>“This doesn’t just apply to Mars … these results have implications in other fields, too,” Mojarro says. Similar methods of DNA sequencing on Earth have been used to help manage and track Ebola outbreaks and in medical research. And further, improvements to SETG could have important implications for planetary protection, which aims to prevent and minimize Earth-originating biological contamination of space environments.</p> <p>Even at the new detection limit for the SETG instrumentation, Mojarro was able to differentiate between human DNA and the <em>Bacillus</em> DNA. “If we detect life on other planets,” Mojarro says, “we need a technique that can tell apart hitchhiking microbes from Earth and Martian life.”</p> <p>In their publication, Mojarro and Carr suggest that these developments may fill in some of the missing gaps in the story of life on Earth. “If there’s life on Mars, there’s a good chance it’s related to us,” Carr says, citing previous studies describing the planetary exchange of materials during the Late Heavy Bombardment period (4.1 to 3.8 billion years ago).</p> <p>If SETG detects and sequences DNA on Mars in the future, Carr says the results could “rewrite our very notion of our own origins.”</p> Shades of Mars: synthetic samples that mimic different regions of our neighboring world. Used to validate life detection protocols, they were synthesized by Angel Mojarro for the SETG team.Photo: C.E. CarrEAPS, School of Science, DNA, Mars, Planetary science, Space exploration, Microchips, Biology, Space, astronomy and planetary science, Research An escape route for carbon Study shows minerals sequester carbon for thousands of years, which may explain oxygen’s abundance in the atmosphere. Wed, 12 Jun 2019 13:00:00 -0400 Jennifer Chu | MIT News Office <p>As many of us may recall from grade school science class, the Earth’s carbon cycle goes something like this: As plants take up carbon dioxide and convert it into organic carbon, they release oxygen back into the air. Complex life forms such as ourselves breathe in this oxygen and respire carbon dioxide. When microbes eat away at decaying plants, they also consume the carbon within, which they convert and release back into the atmosphere as carbon dioxide. And so the cycle continues.</p> <p>The vast majority of the planet’s carbon loops perpetually through this cycle, driven by photosynthesis and respiration. There is, however, a tiny fraction of organic carbon that is continually escaping through a “leak” in the cycle, the cause of which is largely unknown. Scientists do know that, through this leak, some minute amount of carbon is constantly locked away and preserved in the form of rock for hundreds of millions of &nbsp;years.</p> <p>Now, researchers from MIT and elsewhere have found evidence for what may be responsible for carbon’s slow and steady escape route.</p> <p>In a paper published today in the journal <em>Nature</em>, the team reports that organic carbon is leaking out of the carbon cycle mainly due to a mechanism they call “mineral protection.” In this process, carbon, in the form of decomposed bits of plant and phytoplankton material, gloms onto particles of clay and other minerals, for instance at the bottom of a river or ocean, and is preserved in the form of sediments and, ultimately, rock.</p> <p>Mineral protection may also explain why there is oxygen on Earth in the first place: If something causes carbon to leak out of the carbon cycle, this leaves more oxygen to accumulate in the atmosphere.</p> <p>“Fundamentally, this tiny leak is one reason why we exist,” says Daniel Rothman, professor of geophysics in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “It’s what allows oxygen to accumulate over geologic time, and it’s why aerobic organisms evolved, and it has everything to do with the history of life on the planet.”</p> <p>Rothman’s co-authors on the paper include Jordon Hemingway, who led the work as a graduate student at MIT and the Woods Hole Oceanographic Institution and is now a postdoc at Harvard University, along with Katherine Grant, Sarah Rosengard, Timothy Eglinton, Louis Derry, and Valier Galy.</p> <p><strong>Burning dirt</strong></p> <p>Scientists have entertained two main possibilities for how carbon has been leaking out of the Earth’s carbon cycle. The first has to do with “selectivity,” the idea that some types of organic matter, due to their molecular makeup, may be harder to break down than others. Based on this idea, the carbon that is not consumed, and therefore leaks out, has been “selected” to do so, based on the initial organic matter’s molecular structure.</p> <p>The second possibility involves “accessibility,” the notion that some organic matter leaks out of the carbon cycle because it has been made inaccessible for consumption via some secondary process. Some scientists believe that secondary process could be mineral protection — interactions between organic carbon and clay-based minerals that bind the two together in an inaccessible, unconsumable form.</p> <p>To test which of these mechanisms better explains Earth’s carbon leak, Hemingway analyzed sediment samples collected from around the world, each containing organic matter and minerals from a range of river and coastal environments. If mineral preservation is indeed responsible for locking away and preserving carbon over geologic timescales, Hemingway hypothesized that organic carbon bound with clay minerals should last longer in the environment compared with unbound carbon, resisting degradation by foraging microbes, or even other forces such as extreme heat. &nbsp;</p> <p>The researchers tested this idea by burning each sediment sample and measuring the amount and type of organic carbon that remained as they heated the sample at progressively higher temperatures. They did so using a device that Hemingway developed as part of his PhD thesis.</p> <p>“It’s been hypothesized that organic matter that sticks to mineral surfaces will stick around longer in the environment,” Hemingway says. “But there was never a tool to directly quantify that.”</p> <p><strong>“Beating up a natural process”</strong></p> <p>In the end, they found the organic matter that lasted the longest, and withstood the highest temperatures, was bound to clay minerals. Importantly, in a finding that went against the idea of selectivity, it didn’t matter what the molecular structure of that organic matter was — as long as it was bound to clay, it was preserved.</p> <p>The results point to accessibility, and mineral preservation in particular, as the main mechanism for Earth’s carbon leak. In other words, all around the world, clay minerals are slowly and steadily drawing down tiny amounts of carbon, and storing it away for thousands of years.</p> <p>“It’s this clay-bound protection that seems to be the mechanism, and it seems to be a globally coherent phenomenon,” Hemingways says. “It’s a slow leak happening all the time, everywhere. And when you integrate that over geologic timescales, it becomes a really important sink of carbon.”</p> <p>The researchers believe mineral protection has made it possible for vast reservoirs of carbon to be buried and stored in the Earth, some of which has been pressed and heated into petroleum over millions of years. At the Earth’s geologic pace, this carbon preserved in rocks eventually resurfaces through mountain uplift and gradually erodes, releasing carbon dioxide back into the atmosphere ever so slowly.</p> <p>“What we do today with fossil fuel burning is speeding up this natural process,” Rothman says. “We’re getting it out of the ground and burning it right away, and we’re changing the rate at which the carbon that was leaked out is being returned to the system, by a couple orders of magnitude.”</p> <p>Could mineral preservation somehow be harnessed to sequester even more carbon, in an effort to mitigate fossil-fuel-induced climate change?</p> <p>“If we magically had the ability to take a fraction of organic matter in rivers or oceans and attach it to a mineral to hold onto it for 1,000 years, it could have some advantages,” Rothman says. “That’s not the focus of this study. But the longer soils can lock up organic matter, the slower their return to the atmosphere. You can imagine if you could slow that return process down just a little bit, it could make a big difference over 10 to 100 years.”</p> <p>This research was supported, in part, by NASA and the National Science Foundation.</p> A new study finds clay minerals, such as those at the bottom of rivers and oceans, can bind with bits of decomposing plants and phytoplankton in a natural carbon-storing process.Carbon, EAPS, Earth and atmospheric sciences, Environment, Geology, Research, School of Science, NASA, National Science Foundation (NSF), Climate change Algorithm tells robots where nearby humans are headed A new tool for predicting a person’s movement trajectory may help humans and robots work together in close proximity. Mon, 10 Jun 2019 23:59:59 -0400 Jennifer Chu | MIT News Office <p>In 2018, researchers at MIT and the auto manufacturer BMW were testing ways in which humans and robots might work in close proximity to assemble car parts. In a replica of a factory floor setting, the team rigged up a robot on rails, designed to deliver parts between work stations. Meanwhile, human workers crossed its path every so often to work at nearby stations.&nbsp;</p> <p>The robot was programmed to stop momentarily if a person passed by. But the researchers noticed that the robot would often freeze in place, overly cautious, long before a person had crossed its path. If this took place in a real manufacturing setting, such unnecessary pauses could accumulate into significant inefficiencies.</p> <p>The team traced the problem to a limitation in the robot’s trajectory alignment algorithms used by the robot’s motion predicting software. While they could reasonably predict where a person was headed, due to the poor time alignment the algorithms couldn’t anticipate how long that person spent at any point along their predicted path — and in this case, how long it would take for a person to stop, then double back and cross the robot’s path again.</p> <p>Now, members of that same MIT team have come up with a solution: an algorithm that accurately aligns partial trajectories in real-time, allowing motion predictors to accurately anticipate the timing of a person’s motion. When they applied the new algorithm to the BMW factory floor experiments, they found that, instead of freezing in place, the robot simply rolled on and was safely out of the way by the time the person walked by again.</p> <p>“This algorithm builds in components that help a robot understand and monitor stops and overlaps in movement, which are a core part of human motion,” says Julie Shah, associate professor of aeronautics and astronautics at MIT. “This technique is one of the many way we’re working on robots better understanding people.”</p> <p>Shah and her colleagues, including project lead and graduate student Przemyslaw “Pem” Lasota, will present their results this month at the Robotics: Science and Systems conference in Germany.</p> <div class="cms-placeholder-content-video"></div> <p><strong>Clustered up</strong></p> <p>To enable robots to predict human movements, researchers typically borrow algorithms from music and speech processing. These algorithms are designed to align two complete time series, or sets of related data, such as an audio track of a musical performance and a scrolling video of that piece’s musical notation.</p> <p>Researchers have used similar alignment algorithms to sync up real-time and previously recorded measurements of human motion, to predict where a person will be, say, five seconds from now. But unlike music or speech, human motion can be messy and highly variable. Even for repetitive movements, such as reaching across a table to screw in a bolt, one person may move slightly differently each time.</p> <p>Existing algorithms typically take in streaming motion data, in the form of dots representing the position of a person over time, and compare the trajectory of those dots to a library of common trajectories for the given scenario. An algorithm maps a trajectory in terms of the relative distance between dots.</p> <p>But Lasota says algorithms that predict trajectories based on distance alone can get easily confused in certain common situations, such as temporary stops, in which a person pauses before continuing on their path. While paused, dots representing the person’s position can bunch up in the same spot.</p> <p>“When you look at &nbsp;the data, you have a whole bunch of points clustered together when a person is stopped,” Lasota says. “If you’re only looking at the distance between points as your alignment metric, that can be confusing, because they’re all close together, and you don’t have a good idea of which point you have to align to.”</p> <p>The same goes with overlapping trajectories — instances when a person moves back and forth along a similar path. Lasota says that while a person’s current position may line up with a dot on a reference trajectory, existing algorithms can’t differentiate between whether that position is part of a trajectory heading away, or coming back along the same path.</p> <p>“You may have points close together in terms of distance, but in terms of time, a person’s position may actually be far from a reference point,” Lasota says.</p> <p><strong>It’s all in the timing</strong></p> <p>As a solution, Lasota and Shah devised a “partial trajectory” algorithm that aligns segments of a person’s trajectory in real-time with a library of previously collected reference trajectories. Importantly, the new algorithm aligns trajectories in both distance and timing, and in so doing, is able to accurately anticipate stops and overlaps in a person’s path.</p> <p>“Say you’ve executed this much of a motion,” Lasota explains. “Old techniques will say, ‘this is the closest point on this representative trajectory for that motion.’ But since you only completed this much of it in a short amount of time, the timing part of the algorithm will say, ‘based on the timing, it’s unlikely that you’re already on your way back, because you just started your motion.’”</p> <p>The team tested the algorithm on two human motion datasets: one in which a person intermittently crossed a robot’s path in a factory setting (these data were obtained from the team’s experiments with BMW), and another in which the group previously recorded hand movements of participants reaching across a table to install a bolt that a robot would then secure by brushing sealant on the bolt.</p> <p>For both datasets, the team’s algorithm was able to make better estimates of a person’s progress through a trajectory, compared with two commonly used partial trajectory alignment algorithms. Furthermore, the team found that when they integrated the alignment algorithm with their motion predictors, the robot could more accurately anticipate the timing of a person’s motion. In the factory floor scenario, for example, they found the robot was less prone to freezing in place, and instead smoothly resumed its task shortly after a person crossed its path.</p> <p>While the algorithm was evaluated in the context of motion prediction, it can also be used as a preprocessing step for other techniques in the field of human-robot interaction, such as action recognition and gesture detection. Shah says the algorithm will be a key tool in enabling robots to recognize and respond to patterns of human movements and behaviors. Ultimately, this can help humans and robots work together in structured environments, such as factory settings and even, in some cases, the home.</p> <p>“This technique could apply to any environment where humans exhibit typical patterns of behavior,” Shah says. “The key is that the [robotic] system can observe patterns that occur over and over, so that it can learn something about human behavior. This is all in the vein of work of the robot better understand aspects of human motion, to be able to collaborate with us better.”</p> <p>This research was funded, in part, by a NASA Space Technology Research Fellowship and the National Science Foundation.</p> A new algorithm helps robots predict the paths people take in structured environments like the factory floor, which may further enable close collaboration between humans and machines.Aeronautical and astronautical engineering, Algorithms, Artificial intelligence, Assistive technology, Computer modeling, Computer Science and Artificial Intelligence Laboratory (CSAIL), Research, Robots, Robotics, School of Engineering, Machine learning, NASA, National Science Foundation (NSF) Maria Zuber awarded the Gerard P. Kuiper Prize in Planetary Sciences Honor recognizes scientists whose achievements have most advanced our understanding of planetary systems. Fri, 31 May 2019 15:45:01 -0400 EAPS <p><em>The following news is adapted from a&nbsp;press release&nbsp;issued by the Division for Planetary Sciences of the American Astronomical Society.</em></p> <p>The American Astronomical Society’s Division for Planetary Sciences (DPS) has awarded the 2019 Gerard P. Kuiper Prize for outstanding contributions to the field of planetary science to MIT Professor Maria Zuber for her advancements in geophysics, planetary gravity mapping, and laser altimetry. Zuber is the E.A. Griswold Professor of Geophysics in the Department of Earth, Atmospheric and Planetary Sciences (EAPS) and vice president for research at MIT.</p> <p>The Gerard P. Kuiper Prize honors scientists whose lifetime achievements have most advanced society’s understanding of the planetary system. Zuber’s numerous accomplishments include her seminal 2000 paper in <em>Science</em> combining Mars Global Surveyor laser altimetry data and gravity data to determine the crustal and upper mantle structure of Mars. Zuber became the first woman to lead a NASA spacecraft mission as principal investigator of the Gravity Recovery and Interior Laboratory (GRAIL) mission. GRAIL constructed a model of the moon’s gravitational field to spherical harmonic degree 1800, which exceeded the baseline requirement of the mission by an order of magnitude. Zuber has turned her attention to many different solid bodies in the solar system, focusing on structure and tectonics, including Mercury, Venus, Eros, Vesta, and Ceres. Since 1990, she has held leadership roles associated with scientific experiments or instrumentation on nine NASA missions.</p> <p>Zuber has been at the helm of MIT’s research endeavors, overseeing more than a dozen interdisciplinary research laboratories and centers, ensuring intellectual integrity, and fostering research relationships. Over the years, she has advised a number of students and postdocs, and one reports that she strikes the perfect balance of being demanding, supportive, encouraging, and open-minded.&nbsp;</p> <p>As the recipient of the prize, Zuber will be invited to present a lecture at a DPS meeting and publish a written version of it in <em>Icarus</em>.</p> Maria Zuber is the E.A. Griswold Professor of Geophysics in the Department of Earth, Atmospheric and Planetary Sciences (EAPS) and vice president for research at MIT.Photo: Bryce VickmarkAwards, honors and fellowships, Faculty, Planetary science, space, Space, astronomy and planetary science, Moon, Mars, NASA, EAPS, School of Science, Geology MIT team places second in 2019 NASA BIG Idea Challenge Multilevel Mars greenhouse could provide food to sustain astronauts for several years. Mon, 20 May 2019 13:00:01 -0400 Sarah Jensen | Department of Aeronautics and Astronautics <p>An MIT student team took second place for its design of a multilevel greenhouse to be used on Mars in NASA’s 2019 Breakthrough, Innovative and Game-changing (BIG) Idea Challenge last month.&nbsp;</p> <p>Each year, NASA holds the BIG Idea competition in its search for innovative and futuristic ideas. This year’s challenge invited universities across the United States to submit designs for a sustainable, cost-effective, and efficient method of supplying food to astronauts during future crewed explorations of Mars. Dartmouth College was awarded first place in this year’s closely contested challenge.</p> <p>“This was definitely a full-team success,” says team leader Eric Hinterman, a graduate student in MIT’s Department of Aeronautics and Astronautics (AeroAstro). The team had contributions from 10 undergraduates and graduate students from across MIT departments. Support and assistance were provided by four architects and designers in Italy. This project was completely voluntary; all 14 contributors share a similar passion for space exploration and enjoyed working on the challenge in their spare time.</p> <p>The MIT team dubbed its design “BEAVER” (Biosphere Engineered Architecture for Viable Extraterrestrial Residence). “We designed our greenhouse to provide 100 percent of the food requirements for four active astronauts every day for two years,” explains Hinterman.</p> <p>The ecologists and agriculture specialists on the MIT team identified eight types of crops to provide the calories, protein, carbohydrates, and oils and fats that astronauts would need; these included potatoes, rice, wheat, oats, and peanuts. The flexible menu suggested substitutes, depending on astronauts’ specific dietary requirements.</p> <p>“Most space systems are metallic and very robotic,” Hinterman says. “It was fun working on something involving plants.”</p> <p>Parameters provided by NASA — a power budget, dimensions necessary for transporting by rocket, the capacity to provide adequate sustenance — drove the shape and the overall design of the greenhouse.</p> <p>Last October, the team held an initial brainstorming session and pitched project ideas. The iterative process continued until they reached their final design: a cylindrical growing space 11.2 meters in diameter and 13.4 meters tall after deployment.</p> <p><strong>An innovative design</strong></p> <p>The greenhouse would be packaged inside a rocket bound for Mars and, after landing, a waiting robot would move it to its site. Programmed with folding mechanisms, it would then expand horizontally and vertically and begin forming an ice shield around its exterior to protect plants and humans from the intense radiation on the Martian surface.</p> <p>Two years later, when Earth and Mars orbits were again in optimal alignment for launching and landing, a crew would arrive on Mars, where they would complete the greenhouse setup and begin growing crops. “About every two years, the crew would leave and a new crew of four would arrive and continue to use the greenhouse,” explains Hinterman.</p> <p>To maximize space, BEAVER employs a large spiral that moves around a central core within the cylinder. Seedlings are planted at the top and flow down the spiral as they grow. By the time they reach the bottom, the plants are ready for harvesting, and the crew enters at the ground floor to reap the potatoes and peanuts and grains. The planting trays are then moved to the top of the spiral, and the process begins again.</p> <p>“A lot of engineering went into the spiral,” says Hinterman. “Most of it is done without any moving parts or mechanical systems, which makes it ideal for space applications. You don’t want a lot of moving parts or things that can break.”</p> <p><strong>The human factor</strong></p> <p>“One of the big issues with sending humans into space is that they will be confined to seeing the same people every day for a couple of years,” Hinterman explains. “They’ll be living in an enclosed environment with very little personal space.”</p> <p>The greenhouse provides a pleasant area to ensure astronauts’ psychological well-being. On the top floor, just above the spiral, a windowed “mental relaxation area” overlooks the greenery. The ice shield admits natural light, and the crew can lounge on couches and enjoy the view of the Mars landscape. And rather than running pipes from the water tank at the top level down to the crops, Hinterman and his team designed a cascading waterfall at the area’s periphery, further adding to the ambiance.</p> <p>Sophomore Sheila Baber, an Earth, atmospheric, and planetary sciences (EAPS) major and the team’s ecology lead, was eager to take part in the project. “My grandmother used to farm in the mountains in Korea, and I remember going there and picking the crops,” she says. “Coming to MIT, I felt like I was distanced from my roots. I am interested in life sciences and physics and all things space, and this gave me the opportunity to combine all those.”</p> <p>Her work on BEAVER led to Baber’s award of one of five NASA internships at Langley Research Center in Hampton, Virginia this summer. She expects to continue exploration of the greenhouse project and its applications on Earth, such as in urban settings where space for growing food is constrained.</p> <p>“Some of the agricultural decisions that we made about hydroponics and aquaponics could potentially be used in environments on Earth to raise food,” she says.</p> <p>“The MIT team was great to work with,” says Hinterman. “They were very enthusiastic and hardworking, and we came up with a great design as a result.”</p> <p>In addition to Baber and Hinterman, team members included Siranush Babakhanova (Physics), Joe Kusters (AeroAstro), Hans Nowak (Leaders for Global Operations), Tajana Schneiderman (EAPS), Sam Seaman (Architecture), Tommy Smith (System Design and Management), Natasha Stamler (Mechanical Engineering and Urban Studies and Planning), and Zhuchang Zhan (EAPS). Assistance was provided by Italian designers and architects Jana Lukic, Fabio Maffia, Aldo Moccia, and Samuele Sciarretta. The team’s advisors were Jeff Hoffman, Sara Seager, Matt Silver, Vladimir Aerapetian, Valentina Sumini, and George Lordos.</p> <p>The BIG Idea Challenge is sponsored by NASA’s Space Technology Mission Directorate’s Game Changing Development program and managed by the National Institute of Aerospace.</p> MIT team that designed BEAVER (Biosphere Engineered Architecture for Viable Extraterrestrial Residence), a proposed Martian greenhouse that could provide 100 percent of the food required by four astronauts for up to two yearsPhoto: William LitantNASA, Mars, Aeronautical and astronautical engineering, Urban studies and planning, EAPS, Physics, Architecture, Mechanical engineering, Leaders for Global Operations (LGO), System Design and Management, School of Engineering, School of Science, School of Architecture and Planning, Contests and academic competitions, Agriculture, Food, Space exploration MIT, Blue Origin to cooperate on sending research experiment to the moon MIT community input will help determine the focus of the study to be carried aboard Blue Moon lander. Fri, 10 May 2019 17:15:01 -0400 Department of Aeronautics and Astronautics <p>MIT and Blue Origin have signed a memorandum outlining plans to pursue mutual interests in space exploration. MIT will develop one or more payload experiments to be launched aboard Blue Origin’s Blue Moon, a flexible lander delivering a wide variety of small, medium, and large payloads to the lunar surface.</p> <p>MIT Apollo Professor of Astronautics and former NASA Deputy Director Dava Newman, who developed the agreement with Blue Origin, says that over the coming months, MIT researchers will invite input from the MIT community to help determine the nature of the flight opportunity experiment. “Some potential areas include smart habitats, rovers, life support and autonomous systems, human-machine interaction, science of the moon, lunar poles, sample return, and future astronaut performance and suit technologies,” Newman says.</p> <p>Blue Origin’s business development director, A.C. Charania, has said the company’s lunar transportation program is its “first step to developing a lunar landing capability for the country, for other customers internationally, to be able to land multimetric tons on the lunar surface.” Blue Moon payloads could include science experiments, rovers, power systems, and sample return stages.</p> <p>MIT has a long history of aerospace engineering development and lunar science related to space exploration, including receiving the first major contract of the Apollo program, which involved the design and development of the lunar missions’ guidance and navigation computers. MIT experiments have flown on Space Shuttle missions, and been conducted aboard Skylab, Mir, and the International Space Station. MIT also led the GRAIL (Gravity Recovery And Interior Laboratory) mission to explore the moon’s gravity field and geophysical structure.</p> Conceptual image of Blue Origin’s Blue Moon, the proposed robotic space cargo carrier and lander for making cargo deliveries to the MoonIllustration courtesy of Blue Origin.Space, astronomy and planetary science, Aeronautical and astronautical engineering, School of Engineering, Planetary science, Research, Moon Explosions of universe’s first stars spewed powerful jets Instead of ballooning into spheres, as once thought, early supernovae ejected jets that may have seeded new stars. Wed, 08 May 2019 00:00:00 -0400 Jennifer Chu | MIT News Office <p>Several hundred million years after the Big Bang, the very first stars flared into the universe as massively bright accumulations of hydrogen and helium gas. Within the cores of these first stars, extreme, thermonuclear reactions forged the first heavier elements, including carbon, iron, and zinc.</p> <p>These first stars were likely immense, short-lived fireballs, and scientists have assumed that they exploded as similarly spherical supernovae.</p> <p>But now astronomers at MIT and elsewhere have found that these first stars may have blown apart in a more powerful, asymmetric fashion, spewing forth jets that were violent enough to eject heavy elements into neighboring galaxies. These elements ultimately served as seeds for the second generation of stars, some of which can still be observed today.</p> <p>In a paper published today in the <em>Astrophysical Journal</em>, the researchers report a strong abundance of zinc in HE 1327-2326, an ancient, surviving star that is among the universe’s second generation of stars. They believe the star could only have acquired such a large amount of zinc after an asymmetric explosion of one of the very first stars had enriched its birth gas cloud.</p> <p>“When a star explodes, some proportion of that star gets sucked into a black hole like a vacuum cleaner,” says Anna Frebel, an associate professor of physics at MIT and a member of MIT’s Kavli Institute for Astrophysics and Space Research. “Only when you have some kind of mechanism, like a jet that can yank out material, can you observe that material later in a next-generation star. And we believe that’s exactly what could have happened here.”</p> <p><strong>“</strong>This is the first observational evidence that such an asymmetric supernova took place in the early universe,” adds MIT postdoc Rana Ezzeddine, the study’s lead author. “This changes our understanding of how the first stars exploded.”</p> <p><strong>“A sprinkle of elements”</strong></p> <p>HE 1327-2326 was discovered by Frebel in 2005. At the time, the star was the most metal-poor star ever observed, meaning that it had extremely low concentrations of elements heavier than hydrogen and helium — an indication that it formed as part of the second generation of stars, at a time when most of the universe’s heavy element content had yet to be forged.</p> <p>“The first stars were so massive that they had to explode almost immediately,” Frebel says. “The smaller stars that formed as the second generation are still available today, and they preserve the early material left behind by these first stars. Our star has just a sprinkle of elements heavier than hydrogen and helium, so we know it must have formed as part of the second generation of stars.”</p> <p>In May of 2016, the team was able to observe the star which orbits close to Earth, just 5,000 light years away. The researchers won time on NASA’s Hubble Space Telescope over two weeks, and recorded the starlight over multiple orbits. They used an instrument aboard the telescope, the Cosmic Origins Spectrograph, to measure the minute abundances of various elements within the star.</p> <p>The spectrograph is designed with high precision to pick up faint ultraviolet light. Some of those wavelength are absorbed by certain elements, such as zinc. The researchers made a list of heavy elements that they suspected might be within such an ancient star, that they planned to look for in the UV data, including silicon, iron, phosophorous, and zinc.</p> <p>“I remember getting the data, and seeing this zinc line pop out, and we couldn’t believe it, so we redid the analysis again and again,” Ezzeddine recalls. “We found that, no matter how we measured it, we got this really strong abundance of zinc.”</p> <p><strong>A star channel opens</strong></p> <p>Frebel and Ezzeddine then contacted their collaborators in Japan, who specialize in developing simulations of supernovae and the secondary stars that form in their aftermath. The researchers ran over 10,000 simulations of supernovae, each with different explosion energies, configurations, and other parameters. They found that while most of the spherical supernova simulations were able to produce a secondary star with the elemental compositions the researchers observed in HE 1327-2326, none of them reproduced the zinc signal.</p> <p>As it turns out, the only simulation that could explain the star’s makeup, including its high abundance of zinc, was one of an aspherical, jet-ejecting supernova of a first star. Such a supernova would have been extremely explosive, with a power equivalent to about a nonillion times (that’s 10 with 30 zeroes after it) that of a hydrogen bomb.</p> <p>“We found this first supernova was much more energetic than people have thought before, about five to 10 times more,” Ezzeddine says. “In fact, the previous idea of the existence of a dimmer supernova to explain the second-generation stars may soon need to be retired.”</p> <p>The team’s results may shift scientists’ understanding of reionization, a pivotal period during which the gas in the universe morphed from being completely neutral, to ionized — a state that made it possible for galaxies to take shape.</p> <p>“People thought from early observations that the first stars were not so bright or energetic, and so when they exploded, they wouldn’t participate much in reionizing the universe,” Frebel says. “We’re in some sense rectifying this picture and showing, maybe the first stars had enough oomph when they exploded, and maybe now they are strong contenders for contributing to reionization, and for wreaking havoc in their own little dwarf galaxies.”</p> <p>These first supernovae could have also been powerful enough to shoot heavy elements into neighboring “virgin galaxies” that had yet to form any stars of their own.</p> <p>“Once you have some heavy elements in a hydrogen and helium gas, you have a much easier time forming stars, especially little ones,” Frebel says. “The working hypothesis is, maybe second generation stars of this kind formed in these polluted virgin systems, and not in the same system as the supernova explosion itself, which is always what we had assumed, without thinking in any other way. So this is opening up a new channel for early star formation.”</p> <p>This research was funded, in part, by the National Science Foundation.</p> Rana Ezzeddine and Anna Frebel of MIT have observed evidence that the first stars in the universe exploded as asymmetric supernova, strong enough to scatter heavy elements such as zinc across the early universe.Image: Melanie GonickAstronomy, Astrophysics, Kavli Institute, Physics, Research, School of Science, space, Space, astronomy and planetary science Tissue chip headed to International Space Station for osteoarthritis study Successfully launched project aims to understand why some injuries result in post-traumatic osteoarthritis while others heal and recover. Tue, 07 May 2019 12:00:01 -0400 Daniel J. Darling | Department of Biological Engineering <p>On May 4, a National Center for Advancing Translational Sciences (NCATS)-supported tissue-chip system with direct clinical applications to health conditions here on Earth was launched on the SpaceX CRS 17/Falcon 9 rocket.</p> <p>Hundreds of millions of people worldwide suffer from osteoarthritis (OA), and there are currently no disease-modifying drugs that can halt or reverse the progression of OA — only painkillers for short-term symptomatic relief. Millions of healthy young to middle-aged individuals develop post-traumatic osteoarthritis (PTOA) as a result of a traumatic joint injury, like a tear of the anterior cruciate ligament or meniscus, especially in young women playing sports. Exercise-related injuries are also said to be frequent sources of joint injury for crew members living aboard the International Space Station (ISS), and pre-existing joint injuries may also affect astronaut performance in space. These conditions are compounded and worsened by exposure of crew members to weightlessness and radiation on the ISS.</p> <p>After a traumatic joint injury, there is an immediate upregulation of inflammatory proteins called cytokines in the joint synovial fluid, proteins which are secreted mainly by cells in the joint’s synovial lining. When mechanical trauma to cartilage caused by the initial injury is accompanied by cytokine penetration into cartilage, degradation of cartilage and subchondral bone over weeks and months often progresses to full-blown, painful PTOA in 10-15 years.</p> <p>To study PTOA on Earth and in space, investigators at MIT led by Professor Alan Grodzinsky have developed a cartilage-bone-synovium micro-physiological system in which primary human cartilage, bone, and synovium tissues (obtained from donor banks) are co-cultured for several weeks. During culture, investigators can monitor intracellular and extracellular biomarkers of disease using quantitative experimental and computational metabolomics and proteomics analyses, along with detection of disease-specific fragments of tissue matrix molecules. In addition, this co-culture system allows investigators to test the effects of potential disease-modifying drugs to prevent cartilage and bone loss on Earth and in space.</p> <p>Experiments aboard the ISS utilize a Multi-purpose Variable-G Platform, made by Techshot Inc., to study the effects of microgravity and ionizing radiations on a knee tissue chip prepared using cartilage-bone-synovium tissues secured on a biocompatible material. The platform enables automated nutrient media transfer and collection for test conditions with and without disease-modifying drugs, including tests using a one-gravity control system.</p> <p>These investigations on Earth and in the ISS have the potential to lead to the discovery of treatments and treatment regimens that, if administered immediately after a joint injury, could halt the progression of OA disease before it becomes irreversible. The goal is to treat the root cause of PTOA and prevent permanent joint damage, rather than mask the symptoms with painkillers later in life, as is currently done. These studies are funded by the NIH National Center for Advancing Translational Sciences and the <a href="">ISS-National Lab</a>.</p> Sunrise over the International Space StationPhoto: NASABiological engineering, School of Engineering, Tissue engineering, NASA, Space, astronomy and planetary science, Research, Health, Medicine A sustainability rating for space debris Teams from the MIT Media Lab, European Space Agency, and World Economic Forum will create a rating system and global standards for space waste mitigation. Mon, 06 May 2019 14:00:01 -0400 Helen Knight | MIT Media Lab <p>Space is becoming increasingly congested, even as our societal dependence on space technology is greater than ever before.</p> <p>With over 20,000 pieces of debris larger than 10 centimeters, including inactive satellites and discarded rocket parts hurtling around in Earth’s orbit, the risk of damaging collisions increases every year.</p> <p>In a bid to address this issue, and to foster global standards in waste mitigation, the World Economic Forum has chosen a team led by the <a href="">Space Enabled Research Group</a> at the MIT Media Lab, together with a team from the European Space Agency (ESA), to launch the Space Sustainability Rating (SSR), a concept developed by the Forum’s <a href="">Global Future Council on Space Technologies</a>.</p> <p>Similar to rating systems such as the LEED certification used by the construction industry, the SSR is designed to ensure long-term sustainability by encouraging more responsible behavior among countries and companies participating in space.</p> <p>The team, announced on May 6 at the <a href="">Satellite 2019</a> conference in Washington, also includes collaborators from Bryce Space and Technology, and the University of Texas at Austin.</p> <p>The MIT portion of the team will be led by Danielle Wood, the Benesse Corporation Career Development Assistant Professor of Research in Education within MIT’s Program in Media Arts and Sciences, and jointly appointed in the Department of Aeronautics and Astronautics. She will be working alongside Minoo Rathnasabapathy, a research engineer within the Space Enabled group. Professor Moriba Jah and Adjunct Professor Diane Howard contribute from the <a href="">University of Texas at Austin</a> building on Professor Jah’s in-depth research on tracking and visualizing space objects and Professor Howard’s legal knowledge, while Mike French and Aschley Schiller bring expertise about space industry dynamics from <a href="">Bryce</a>. The MIT-led team joins the efforts of Nikolai Khlystov and Maksim Soshkin in the World Economic Forum Aerospace Industry Team as well as Stijn Lemmens and Francesca Letzia in the <a href="">Space Debris Office</a> of the European Space Agency.</p> <p>Working with the World Economic Forum and the other collaborators to create the SSR is directly in line with the mission of the Media Lab's Space Enabled research group, of which Wood is also the founder and head, to advance justice in Earth's complex systems using designs enabled by space.</p> <p>“One element of justice is ensuring that every country has the opportunity to participate in using space technology as a form of infrastructure to provide vital services in our society such as communication, navigation, and environmental monitoring,” Wood says.</p> <p>Many aspects of modern society depend on satellite services. Weather reports, for example, depend on a global network of weather satellites operated primarily by governments.</p> <p>In addition, car drivers, trains, ships and airplanes routinely use satellite positioning services. These same positioning satellites also offer a highly accurate timing signal used by the global banking system to precisely time financial transactions.</p> <p>“Our global economy depends on our ability to operate satellites safely in order to fly in planes, prepare for severe weather, broadcast television and study our changing climate,” Wood says. “To continue using satellites in orbit around Earth for years to come, we need to ensure that the environment around Earth is as free as possible from trash leftover from previous missions.”</p> <p>When satellites are retired from useful service, many will remain in orbit for decades longer, adding to the problem of space debris.</p> <p>In the best case scenario, satellites will gradually drift down to lower orbits and burn up in Earth's atmosphere. However, the higher the orbit a satellite is operating in, the longer it takes to move down and burn up.</p> <p>When satellite operators design their satellites, they are able to choose which altitude to use, and for how long their spacecraft will operate. They therefore have a responsibility to design their satellites to produce as little waste as possible in Earth's orbit.</p> <p>“The Space Sustainability Rating will create an incentive for companies and governments operating satellites to take all the steps they can to reduce the creation of space debris,” Wood says. “This will create a more equitable opportunity for new countries to participate in space with less risk of collision with older satellites.”</p> <p>Many governments already provide guidelines to companies operating within their borders, to help reduce the amount of space debris produced. The space community is also engaged in an ongoing discussion about new ways to reduce the creation of debris.</p> <p>But in the meantime, multiple companies are planning to launch large constellations of satellites that will quickly increase the number of spacecraft in orbit. These satellite constellations will eventually be decommissioned, adding to the growing space junk problem.</p> <p>To address this issue, the World Economic Forum Global Future Council on Space Technologies, which is composed of leaders from government, academia and industry, has developed the concept of a voluntary system, the SSR, to encourage those who operate satellites to create as little debris as possible.</p> <p>The newly announced team will draw up the rules and processes by which the SSR will operate, including determining what information should be collected from satellite operators to assess their impact on space sustainability.</p> <p>“Countries in every region are starting new space programs to participate in applying space to their national development,” Wood says. “Creating the Space Sustainability Rating with our collaborators is one key step to ensure that all countries continue to increase the benefits we receive from space technology," she says.</p> <p>With a lack of diversity in existing strategies to tackle the orbital debris challenge, the Global Future Council felt it important to develop an industry-wide approach, according to Nikolai Khlystov, lead for aerospace industry at the World Economic Forum.</p> <p>“We are very glad to partner with leading industry entities such as the European Space Agency, MIT's Space Enabled research group, the University of Texas at Austin and Bryce Space and Technology to build and launch the Space Sustainability Rating,” Khlystov says.</p> <p>The envisaged SSR has as clear goal to promote mission designs and operational concepts that avoid an unhampered growth in space debris and the resulting detrimental effects, says Stijn Lemmens, senior space debris mitigation analyst in the Space Debris Office at ESA.</p> <p>“Together with our collaborators, we aim to put in place a system that has the flexibility to stimulate and drive innovative sustainable design solutions, and spotlight those missions that contribute positively to the space environment,” Lemmens says.</p> In orbit around Earth today there are over 20,000 objects larger than 10 centimeters. Of these, only about 2000 are operational satellites. The remainder are space debris that create a hazard for the useful satellites that provide our global weather, navigation, and communication services. Image: European Space AgencyAeronautical and astronautical engineering, School of Architecture and Planning, Media Lab, Satellites, Space, astronomy and planetary science, Technology and society, Policy North Atlantic Ocean productivity has dropped 10 percent during Industrial era Phytoplankton decline coincides with warming temperatures over the last 150 years. Mon, 06 May 2019 12:04:06 -0400 Jennifer Chu | MIT News Office <p>Virtually all marine life depends on the productivity of phytoplankton — microscopic organisms that work tirelessly at the ocean’s surface to absorb the carbon dioxide that gets dissolved into the upper ocean from the atmosphere.</p> <p>Through photosynthesis, these microbes break down carbon dioxide into oxygen, some of which ultimately gets released back to the atmosphere, and organic carbon, which they store until they themselves are consumed. This plankton-derived carbon fuels the rest of the marine food web, from the tiniest shrimp to giant sea turtles and humpback whales.</p> <p>Now, scientists at MIT, Woods Hole Oceanographic Institution (WHOI), and elsewhere have found evidence that phytoplankton’s productivity is declining steadily in the North Atlantic, one of the world’s most productive marine basins.</p> <p>In a paper appearing today in <em>Nature</em>, the researchers report that phytoplankton’s productivity in this important region has gone down around 10 percent since the mid-19th century and the start of the Industrial era. This decline coincides with steadily rising surface temperatures over the same period of time.</p> <p>Matthew Osman, the paper’s lead author and a graduate student in MIT’s Department of Earth, Atmospheric, and Planetary Sciences and the MIT/WHOI Joint Program in Oceanography, says there are indications that phytoplankton’s productivity may decline further as temperatures continue to rise as a result of human-induced climate change.</p> <p>“It’s a significant enough decine that we should be concerned,” Osman says. “The amount of productivity in the oceans roughly scales with how much phytoplankton you have. So this translates to 10 percent of the marine food base in this region that’s been lost over the industrial era. If we have a growing population but a decreasing food base, at some point we’re likely going to feel the effects of that decline.”</p> <p><strong>Drilling through “pancakes” of ice</strong></p> <p>Osman and his colleagues looked for trends in phytoplankton’s productivity using the molecular compound methanesulfonic acid, or MSA. When phytoplankton expand into large blooms, certain microbes emit dimethylsulfide, or DMS, an aerosol that is lofted into the atmosphere and eventually breaks down as either sulfate aerosol, or MSA, which is then deposited on sea or land surfaces by winds.</p> <p>“Unlike sulfate, which can have many sources in the atmosphere, it was recognized about 30 years ago that MSA had a very unique aspect to it, which is that it’s only derived from DMS, which in turn is only derived from these phytoplankton blooms,” Osman says. “So any MSA you measure, you can be confident has only one unique source — phytoplankton.”</p> <p>In the North Atlantic, phytoplankton likely produced MSA that was deposited to the north, including across Greenland. The researchers measured MSA in Greenland ice cores — in this case using 100- to 200-meter-long columns of snow and ice that represent layers of past snowfall events preserved over hundreds of years.</p> <p>“They’re basically sedimentary layers of ice that have been stacked on top of each other over centuries, like pancakes,” Osman says.</p> <p>The team analyzed 12 ice cores in all, each collected from a different location on the Greenland ice sheet by various groups from the 1980s to the present. Osman and his advisor Sarah Das, an associate scientist at WHOI and co-author on the paper, collected one of the cores during an expedition in April 2015.</p> <p>“The conditions can be really harsh,” Osman says. “It’s minus 30 degrees Celsius, windy, and there are often whiteout conditions in a snowstorm, where it’s difficult to differentiate the sky from the ice sheet itself.”</p> <p>The team was nevertheless able to extract, meter by meter, a 100-meter-long core, using a giant drill that was delivered to the team’s location via a small ski-equipped airplane. They immediately archived each ice core segment in a heavily insulated cold storage box, then flew the boxes on “cold deck flights” — aircraft with ambient conditions of around minus 20 degrees Celsius. Once the planes touched down, freezer trucks transported the ice cores to the scientists’ ice core laboratories.</p> <p>“The whole process of how one safely transports a 100-meter section of ice from Greenland, kept at minus-20-degree conditions, &nbsp;back to the United States is a massive undertaking,” Osman says.</p> <p><strong>Cascading effects</strong></p> <p>The team incorporated the expertise of researchers at various labs around the world in analyzing each of the 12 ice cores for MSA. Across all 12 records, they observed a conspicuous decline in MSA concentrations, beginning in the mid-19th century, around the start of the Industrial era when the widescale production of greenhouse gases began. This decline in MSA is directly related to a decline in phytoplankton productivity in the North Atlantic.</p> <p>“This is the first time we’ve collectively used these ice core MSA records from all across Greenland, &nbsp;and they show this coherent signal. We see a long-term decline that originates around the same time as when we started perturbing the climate system with industrial-scale greenhouse-gas emissions,” Osman says. “The North Atlantic is such a productive area, and there’s a huge multinational fisheries economy related to this productivity. Any changes at the base of this food chain will have cascading effects that we’ll ultimately feel at our dinner tables.”</p> <p>The multicentury decline in phytoplankton productivity appears to coincide not only with concurrent long-term warming temperatures; it also shows synchronous variations on decadal time-scales with the large-scale ocean circulation pattern known as the Atlantic Meridional Overturning Circulation, or AMOC. This circulation pattern typically acts to mix layers of the deep ocean with the surface, allowing the exchange of much-needed nutrients on which phytoplankton feed.</p> <p>In recent years, scientists have found evidence that AMOC is weakening, a process that is still not well-understood but may be due in part to warming temperatures increasing the melting of Greenland’s ice. This ice melt has added an influx of less-dense freshwater to the North Atlantic, which acts to stratify, or separate its layers, much like oil and water, preventing nutrients in the deep from upwelling to the surface. This warming-induced weakening of the ocean circulation could be what is driving phytoplankton’s decline. As the atmosphere warms the upper ocean in general, this could also further the ocean’s stratification, worsening phytoplankton’s productivity.</p> <p>“It’s a one-two punch,” Osman says. “It’s not good news, but the upshot to this is that we can no longer claim ignorance. We have evidence that this is happening, and that’s the first step you inherently have to take toward fixing the problem, however we do that.”</p> <p>This research was supported in part by the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), as well as graduate fellowship support from the US Department of Defense Office of Naval Research.</p> Ice core field camp on a clear spring evening, Disko Island Ice Cap, west Greenland. Image: Luke Trusel (Rowan University)Climate, Climate change, EAPS, Earth and atmospheric sciences, Environment, Global Warming, Greenhouse gases, Oceanography and ocean engineering, Research, School of Science, National Science Foundation (NSF), NASA Six suborbital research payloads from MIT fly to space and back Space Exploration Initiative research aboard Blue Origin’s New Shepard experiment capsule crossed the Karman line for three minutes of sustained microgravity. Fri, 03 May 2019 14:50:40 -0400 Stephanie Strom | MIT Media Lab <p>Blast off! MIT made its latest foray into research in space on May 2 via six payloads from the Media Lab Space Exploration Initiative, tucked into Blue Origin’s New Shepard reusable space vehicle that took off from a launchpad in West Texas.</p> <p>It was also the first time in the history of the Media Lab that in-house research projects were launched into space, for several minutes of sustained microgravity. The results of that research may have big implications for semiconductor manufacturing, art and telepresence, architecture and farming, among other things.</p> <p>“The projects we’re testing operate fundamentally different in Earth’s gravity compared to how they would operate in microgravity,” explained Ariel Ekblaw, the founder and lead of the Media Lab’s Space Exploration Initiative.</p> <p>Previously, the Media Lab sent projects into microgravity aboard the plane used by NASA to train astronauts, lovingly nicknamed “the vomit comet.” These parabolic flights provide repeated 15 to 30 second intervals of near weightlessness. The New Shepard experiment capsule will coast in microgravity for significantly longer and cross the Karman line (the formal boundary of “space”) in the process. While that may not seem like much time, it’s enough to get a lot accomplished.</p> <p>“The capsule where the research takes place arcs through space for three minutes, which gives us precious moments of sustained, high quality microgravity,” Ekblaw said. “This provides an opportunity to expand our experiments from prior parabolic flight protocols, and test entirely new research as well.”</p> <p>Depending on the results of the experiments done during New Shepard’s flight, some of the projects will undergo further, long-term research aboard the International Space Station, Ekblaw said.</p> <p>On this trip, she sent Tessellated Electromagnetic Space Structures for the Exploration of Reconfigurable, Adaptive Environments, otherwise known as TESSERAE, into space. The ultimate goal for these sensor-augmented hexagonal and pentagonal &nbsp;“tiles” is to autonomously self-assemble into space structures. These flexible, reconfigurable modules can then be used for habitat construction, in-space assembly of satellites, or even as infrastructure for parabolic mirrors. Ekblaw hopes TESSERAE will one day support in-orbit staging bases for human exploration of the surface of the moon or Mars, or enable low Earth orbit space tourism.</p> <p>An earlier prototype, flown on a parabolic flight in November 2017, validated the research concept mechanical structure, polarity arrangement of bonding magnets, and the self-assembly physical protocol. On the Blue Origin flight, Ekblaw is testing a new embedded sensor network in the tiles, as well as their communication architecture and guidance control aspects of their self-assembly capabilities. “We’re testing whether they’ll autonomously circulate, find correct neighbors, and bond together magnetically in microgravity for robust self-assembly,” Ekblaw said.</p> <p>Another experiment aboard New Shepard combined art with the test of a tool for future space exploration — traversing microgravity with augmented mobility. Living Distance, an artwork conceived by the Space Exploration Initiative’s art curator, Xin Liu, explores freedom of movement via a wisdom tooth — yes, you read that correctly!</p> <p>The tooth traveled to space carried by a robotic device named EBIFA and encased in a crystalline container. Once New Shepard entered space, the container burst open and EBIFA swung into action, shooting cords out with magnetic tips to latch onto a metal surface. The tooth then floated through space with minimal interference in the virtually zero-gravity environment.</p> <p>“In this journey, the tooth became a newborn entity in space, its crystalline, sculptural body and life supported by an electromechanical system,” Xin Liu wrote. “Each of its weightless movements was carefully calculated on paper and modeled in simulation software, as there can never be a true test like this on Earth.”</p> <p>The piece builds on a performance art work called Orbit Weaver that Liu performed last year during a parabolic flight, where she was physically tethered to a nylon cord that floated freely and attached to nearby surfaces. Orbit Weaver and Living Distance may offer insights to future human space explorers about how best to navigate weightlessness.</p> <p>A piece of charcoal also made the trip to space inside a chamber lined with drawing paper, part of a project designed by Ani Liu, a Media Lab alumna. In microgravity, the charcoal will chart its own course inside the chamber, marking the paper as it floats through an arc far above the Earth.</p> <p>When the chamber returns to the Media Lab, the charcoal will join forces with a KUKA robot that will mimic the charcoal’s trajectory during the three-ish minutes of coasting in microgravity. Together, the charcoal and the robot will become a museum exhibit that provides a demonstration of motion in microgravity to a broad audience and illustrates the Space Exploration Initiative’s aim to democratize access to space and invite the public to engage in space exploration.</p> <p>Harpreet Sareen, another Media Lab alum, tested how crystals form in microgravity, research that may eventually lead to manufacturing semiconductors in space.</p> <p>Semiconductors used in today’s technology require crystals with extremely high levels of purity and perfect shapes, but gravity interferes with crystal growth on Earth, resulting in faults, contact stresses, and other flaws. Sareen and his collaborator, Anna Garbier, created a nano-sized lab in a box a little smaller than a half-gallon milk carton. The electric current that kicked off growth of the crystals during the three minutes the New Shepard capsule was suborbital was triggered by onboard rocket commands from Blue Origin.</p> <p>The crystals will be evaluated for potential industrial applications, and they also have a future as an art installation: Floral Cosmonauts.</p> <p>And then there are the 40 or so bees (one might say “apionauts”) that made the trip into space on behalf of the Mediated Matter group at the Media Lab, which is interested in seeing the impact space travel has on a queen bee and her retinue. Two queen bees that were inseminated at a U.S. Department of Agriculture facility in Louisiana went to space, each with roughly 20 attendant bees whose job it was to feed her and help control her body temperature.</p> <p>The bees traveled via two small containers — metabolic support capsules — into which they previously built honeycomb structures. This unique design gives them a familiar environment for their trip. A modified GoPro camera, pointed into the specially designed container housing the bees, was fitted into the top of the case to film the insects and create a record of their behavior during flight.</p> <p>Everything inside the case was designed to make the journey as comfortable as possible for the bees, right down to a tiny golden heating pad that was to kick into action if the temperature dropped too low for a queen bee’s comfort.</p> <p>Researchers in the Mediated Matter group will study the behavior of the bees when they return to Earth and are reintroduced to a colony at the Media Lab. Will the queens lay their eggs? Will those eggs hatch? And can bees who’ve been to space continue making pollen and honey once they’ve returned to Earth? Those are among the many questions the team will be asking.</p> <p>“We currently have no robotic alternative to bees for pollination of many crops,” Ekblaw said. “If we want to grow crops on Mars, we may need to bring bees with us. Knowing if they can survive a mission, reintegrate into the hive, and thrive afterwards is critical.”</p> <p>As these projects show, the Space Exploration Initiative unites engineers, scientists, artists, and designers across a multifaceted research portfolio. The team looks forward to a regular launch cadence and progressing through microgravity research milestones — from parabolic flights, to further launch opportunities with Blue Origin, to the International Space Station and even lunar landings.</p> MIT Media Lab researchers (l-r) Xin Liu, Felix Kraemer, Ariel Ekblaw, Pete Dilworth, Rachel Smith, and Harpreet Sareen stand in front of the Blue Origin capsule holding their six payloads.Media Lab, Space, astronomy and planetary science, Research, Industry, School of Architecture and Planning, Arts, Materials Science and Engineering, Architecture, Agriculture, Manufacturing, Aeronautical and astronautical engineering LIGO and Virgo detect neutron star smash-ups Findings reported just weeks into the network’s latest operating run. (Press release) Thu, 02 May 2019 08:00:00 -0400 MIT News Office <p><em>The following press release was issued jointly today by the LIGO Laboratory, LIGO Scientific Collaboration, and Virgo Collaboration.</em></p> <p>On April 25, 2019, the National Science Foundation's Laser Interferometer Gravitational-Wave Observatory (LIGO) and the European-based Virgo detector registered gravitational waves from what appears likely to be a crash between two neutron stars — the dense remnants of massive stars that previously exploded. One day later, on April 26, the LIGO-Virgo network spotted another candidate source with a potentially interesting twist: It may in fact have resulted from the collision of a neutron star and black hole, an event never before witnessed.</p> <p>"The universe is keeping us on our toes," says Patrick Brady, spokesperson for the LIGO Scientific Collaboration and a professor of physics at the University of Wisconsin-Milwaukee. "We're especially curious about the April 26 candidate. Unfortunately, the signal is rather weak. It's like listening to somebody whisper a word in a busy café; it can be difficult to make out the word or even to be sure that the person whispered at all. It will take some time to reach a conclusion about this candidate."</p> <p>"NSF's LIGO, in collaboration with Virgo, has opened up the universe to future generations of scientists," says NSF Director France Cordova. "Once again, we have witnessed the remarkable phenomenon of a neutron star merger, followed up closely by another possible merger of collapsed stars. With these new discoveries, we see the LIGO-Virgo collaborations realizing their potential of regularly producing discoveries that were once impossible. The data from these discoveries, and others sure to follow, will help the scientific community revolutionize our understanding of the invisible universe."</p> <p>The discoveries come just weeks after <a href="">LIGO and Virgo turned back on</a>. The twin detectors of LIGO — one in Washington and one in Louisiana — along with Virgo, located at the European Gravitational Observatory (EGO) in Italy, resumed operations April 1, after undergoing a series of upgrades to increase their sensitivities to gravitational waves — ripples in space and time. Each detector now surveys larger volumes of the universe than before, searching for extreme events such as smash-ups between black holes and neutron stars.</p> <p>"Joining human forces and instruments across the LIGO and Virgo collaborations has been once again the recipe of an incomparable scientific month, and the current observing run will comprise 11 more months," says Giovanni Prodi, the Virgo data analysis coordinator, at the University of Trento and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. "The Virgo detector works with the highest stability, covering the sky 90 percent of the time with useful data. This is helping in pointing to the sources, both when the network is in full operation&nbsp;and at times when only one of the LIGO detectors is operating. We have a lot of groundbreaking research work ahead."</p> <p>In addition to the two new candidates involving neutron stars, the LIGO-Virgo network has, in this latest run, spotted three likely black hole mergers. In total, since making history with the <a href="">first-ever direct detection of gravitational waves</a> in 2015, the network has spotted evidence for two neutron star mergers; 13 black hole mergers; and one possible black hole-neutron star merger.</p> <p>When two black holes collide, they warp the fabric of space and time, producing gravitational waves. When two neutron stars collide, they not only send out gravitational waves but also light. That means telescopes sensitive to light waves across the electromagnetic spectrum can witness these fiery impacts together with LIGO and Virgo. <a href="">One such event occurred in August 2017</a>: &nbsp;LIGO and Virgo initially spotted a neutron star merger in gravitational waves and then, in the days and months that followed, about 70 telescopes on the ground and in space witnessed the explosive aftermath in light waves, including everything from gamma rays to optical light to radio waves.</p> <p>In the case of the two recent neutron star candidates, telescopes around the world once again raced to track the sources and pick up the light expected to arise from these mergers. Hundreds of astronomers eagerly pointed telescopes at patches of sky suspected to house the signal sources. However, at this time, neither of the sources has been pinpointed.</p> <p>"The search for explosive counterparts of the gravitational-wave signal is challenging due to the amount of sky that must be covered and the rapid changes in brightness that are expected," says Brady. "The rate of neutron star merger candidates being found with LIGO and Virgo will give more opportunities to search for the explosions over the next year."</p> <p>The April 25 neutron star smash-up, dubbed S190425z, is estimated to have occurred about 500 million light-years away from Earth. Only one of the twin LIGO facilities picked up its signal along with Virgo (LIGO Livingston witnessed the event but LIGO Hanford was offline). Because only two of the three detectors registered the signal, estimates of the location in the sky from which it originated were not precise, leaving astronomers to survey nearly one-quarter of the sky for the source.</p> <p>The possible April 26 neutron star-black hole collision (referred to as S190426c) is estimated to have taken place roughly 1.2 billion light-years away. It was seen by all three LIGO-Virgo facilities, which helped better narrow its location to regions covering about 1,100 square degrees, or about 3 percent of the total sky.</p> <p>"The latest LIGO-Virgo observing run is proving to be the most exciting one so far," says David H. Reitze of Caltech, executive director of LIGO. "We're already seeing hints of the first observation of a black hole swallowing a neutron star. If it holds up, this would be a trifecta for LIGO and Virgo — in three years, we'll have observed every type of black hole and neutron star collision. But we've learned that claims of detections require a tremendous amount of painstaking work — checking and rechecking — so we'll have to see where the data takes us."</p> <p>LIGO is funded by NSF and operated by Caltech and MIT, which conceived of LIGO and led the Initial and Advanced LIGO projects. Financial support for the Advanced LIGO project was led by the NSF with Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council) and Australia (Australian Research Council-OzGrav) making significant commitments and contributions to the project. Approximately 1,300 scientists from around the world participate in the effort through the LIGO Scientific Collaboration, which includes the GEO Collaboration. A list of additional partners is available at&nbsp;<a href=""><strong></strong></a>.</p> <p>The Virgo Collaboration is currently composed of approximately 350 scientists, engineers, and technicians from about 70 institutes from Belgium, France, Germany, Hungary, Italy, the Netherlands, Poland, and Spain. The European Gravitational Observatory (EGO) hosts the Virgo detector near Pisa in Italy, and is funded by Centre National de la Recherche Scientifique (CNRS) in France, the Istituto Nazionale di Fisica Nucleare (INFN) in Italy, and Nikhef in the Netherlands. A list of the Virgo Collaboration members can be found at&nbsp;<a href=""><strong></strong></a>. More information is available on the Virgo website at&nbsp;<a href=""><strong></strong></a></p> An artist’s illustration of two colliding neutron stars.Image: NASA/Swift/Dana BerryAstronomy, Astrophysics, Gravitational waves, LIGO, Kavli Institute, Physics, Research, School of Science, Black holes, National Science Foundation (NSF) 3 Questions: Salvatore Vitale on LIGO’s latest detections “We will keep listening for these faint and remote cosmic whispers,” says the physics professor. Thu, 02 May 2019 07:59:59 -0400 Jennifer Chu | MIT News Office <p><em>It’s been just three weeks since LIGO <a href="">resumed its hunt</a> for cosmic ripples through space-time, and already the gravitational-wave hunter is off to a running start.</em></p> <p><em>One of the detections researchers are now poring over is a binary neutron star merger — a collision of two incredibly dense stars, nearly 500 million light years away. The power of this stellar impact set off gravitational waves across the cosmos, eventually reaching Earth as infinitely small ripples that were picked up by LIGO (the Laser Interferometer Gravitational-wave Observatory, operated jointly by Caltech and MIT), as well as by Virgo, LIGO’s counterpart in Italy, on April 25 at 4 a.m. ET.</em></p> <em>Researchers have determined that the source of the gravitational wave signal is likely a binary neutron star merger, which they’ve dubbed #S190425z. This is the second time that LIGO has discovered such a source. </em> <p><em>The other neutron star merger, <a href="">detected in 2017</a>, was also the </em><em>first event captured by LIGO that was also observed using optical telescopes. As astronomers around the world pointed telescopes at this first neutron star merger, they were able to see the brilliant “kilonova” explosion generated as the two stars merged. They also detected signatures of gold and platinum in the aftermath — direct evidence for how heavy elements are produced in the universe. </em></p> <p><em>With LIGO’s new detection, astronomers are again pointing telescopes to the skies and searching for optical traces of the stellar merger and any resulting cosmic goldmine. </em></p> <p>MIT News<em> caught up with Salvatore Vitale, assistant professor of physics at MIT and a member of the LIGO Scientific Collaboration, about this newest stellar discovery and hints of even more “cosmic whispers” on the horizon — including the tantalizing possibility that LIGO has also captured the collision of a black hole and a neutron star.</em></p> <p><strong>Q:</strong> Walk us through the moment of discovery. When did this signal come in, and what told you that it was likely a binary neutron star merger?</p> <p><strong>A:</strong> The signal hit Earth at 4:18 a.m. EDT. Unfortunately, at that time the LIGO detector in Hanford, Washington, was not collecting data. The signal was thus detected by the LIGO instrument in Baton Rouge, Louisiana, and the Virgo detector in Italy. Having only two detectors online did not affect our confidence of it being real, since neutron star binaries spend more than one minute in our detectors and these kinds of very long chirps cannot easily be confused with instrumental artifacts or other sources of noise. Similarly, we were able to measure extremely well the mass of the source, which told us it was a binary neutron star, the second ever detected by LIGO and Virgo.</p> <p>The main consequence of only having two detectors online was that it hurt our ability to localize the source in the sky. The sky map we sent out had a very large uncertainty, over 10,000 square degrees, which is a huge area to follow up, if you are looking for an electromagnetic counterpart.</p> <p><strong>Q:</strong> Since the notice from LIGO went out, astronomers have been training telescopes on the sky. What have they been able to find about this new merger, and how is it different from the one LIGO detected in 2017?</p> <p><strong>A:</strong> When two neutron stars smash one against the other, they trigger a cataclysmic explosion that releases huge amounts of energy and creates some of the heaviest elements in the universe (gold, among others). Finding both gravitational and electromagnetic waves can tell us about the environment in which these systems form, how they shine, their role in enriching galaxies with metals, and about the universe. This is why we routinely and automatically send public alerts to astronomers, so that they can try to identify the sources of our gravitational-wave events.</p> <p>This is challenging for S190425z, since it has been localized poorly (compare 10,000 square degrees for S190425z with 30 square degrees for the first binary neutron star&nbsp; merger, GW170817). Another important difference is that S190425z was nearly four times further away. Both these factors make it harder to successfully find an electromagnetic counterpart to S190425z. You want to scan a much larger area, and you want to find a weaker and more distant source. This doesn’t mean that astronomers are not trying hard! In fact, in the last 36 hours there have been dozens of observations. So far nothing too convincing, but a lot of excitement! It is nice to see the broader community so engaged with the follow-up of LIGO and Virgo’s events.<br /> <br /> <strong>Q:</strong> Since it started its newest observing run, LIGO has been detecting at least one gravitational wave source per week. What does this say about what sort of extreme phenomena are happening in the universe, on a daily basis?</p> <p><strong>A: </strong>The last few weeks have been incredibly exciting! So far we are making discoveries at roughly the rate we were expecting: one binary black hole a week and one binary neutron star a month. This confirms our expectations that gravitational waves can really play a major role in understanding the most extreme objects of the universe.</p> <p>It also says that it is not uncommon that two stellar-mass black holes merge, which was not obvious at all before LIGO and Virgo discovered them. We still don’t know if the black holes pairs we are seeing had been together their whole cosmic life, first as normal stars, then as black holes, or if instead they were born separately and then just happened to meet and form a binary system. Both avenues are possible, and with a few more tens of detections we should be able to tell which of these two scenarios happens more often.</p> <p>Then there is always the possibility of detecting something new and unexpected! As I started drafting these answers, we detected <a href="">#S190426c</a>, which, if of astrophysical origin, could be the first neutron star colliding into a black hole ever detected by humans. We will know more in the next few weeks, and we will keep listening for these faint and remote cosmic whispers.</p> Salvatore Vitale, assistant professor of physics at MIT and member of the LIGO Scientific CollaborationCourtesy of MIT Kavli Institute for Astrophysics and Space ResearchAstronomy, Astrophysics, Gravitational waves, LIGO, Kavli Institute, Physics, Research, School of Science, Black holes, National Science Foundation (NSF) Quantum measurement could improve gravitational wave detection sensitivity Research could enable a new suite of experiments to measure quantum activity at room temperature. Wed, 01 May 2019 12:30:01 -0400 Brittany Flaherty | School of Science <p>Minutes before dawn on Sept. 14, 2015, the Laser Interferometer Gravitational-wave Observatory (LIGO) became the <a href="">first-ever instrument on Earth to directly detect a gravitational wave</a>. This work, led by the LIGO Scientific Collaboration&nbsp;with prominent roles from MIT and Caltech, was the first confirmation of this consequence of Albert Einstein’s theory of general relativity — 100 years after he first predicted it. The groundbreaking detection represented an enormous step forward in the field of astrophysics. In the years since, scientists have striven to achieve even greater sensitivity in the LIGO detectors.</p> <p>New research has taken investigators one step closer to this goal. Nergis Mavalvala, the Curtis and Kathleen Marble Professor of Astrophysics at MIT, postdoc Robert Lanza, graduate student Nancy Aggarwal, and their collaborators at Louisiana State University (LSU) recently conducted experiments that could help overcome a future limitation in Advanced LIGO. In their laboratory study, the team successfully measured a type of noise that will soon hold the LIGO instruments back from detecting gravitational waves with greater sensitivity.</p> <p>Their study, <a href="">reported recently in <em>Nature</em></a>, was the first to measure an important source of quantum noise at room temperature and at frequencies relevant to gravitational wave detectors. Funded by the National Science Foundation, this work could enable researchers to understand this limiting noise source and test ideas for circumventing it to further increase LIGO’s sensitivity to gravitational waves.</p> <p>In addition to future applications for improving LIGO’s detection abilities, Mavalvala says these observations of quantum effects at room temperature could help scientists learn more about how quantum mechanics can disturb the precision of measurements generally — and how best to get around these quantum noise limits.</p> <p>“This result was important for the gravitational wave community,” says Mavalvala. “But more broadly, this is essentially a room-temperature quantum resource, and that's something that many communities should care about.”</p> <p><strong>Sensitivity upgrade</strong></p> <p>LIGO has undergone upgrades since its first gravitational wave searches in 2002; the currently operating version of the instrumentation is called Advanced LIGO following major upgrades in 2015. But to get LIGO to its maximum design sensitivity, Mavalvala says her team needs to be able to conduct experiments and test improvement strategies in the laboratory rather than on the LIGO instruments themselves. LIGO’s astrophysical detection work is too important to interfere with, so she and her collaborators have developed instruments in the lab that can mimic the sensitivity of the real thing. In this case, the team aimed to reproduce processes that occur in LIGO to measure a type of noise called quantum radiation pressure noise (QRPN).</p> <p>In LIGO, gravitational waves are detected by using lasers to probe the motion of mirrors. The mirrors are suspended as pendulums, allowing them to have periodic motion similar to a mass on a spring. When laser beams hit the movable mirrors, the momentum carried by the light applies pressure on the mirror and causes them to move slightly.</p> <p>“I like to think of it like a pool table,” says Aggarwal. “When your white cue ball strikes the ball in front of it, the cue ball comes back but it still moves the other ball. When a photon that was traveling forward then travels backwards, the momentum went somewhere; [in this case] that momentum went into the mirror.”</p> <p>The quantum nature of light, which is made up of photons, dictates that there are quantum fluctuations in the number of photons hitting the mirrors, creating an uncertain amount of force on the mirrors at any given moment. This uncertainty results in random perturbations of the mirror. When the laser power is high enough, this QRPN can interfere with gravitational wave detection. At Advanced LIGO’s full design sensitivity, with many hundreds of kilowatts of laser power hitting 40-kilogram mirrors, QRPN will become a dominant limitation.</p> <p><strong>Minuscule mirrors</strong></p> <p>To address this imminent issue, Mavalvala, Aggarwal, and their collaborators designed an experiment to recreate the effects of QRPN in a laboratory setting. One challenge was that the team could not use lasers as powerful as those in Advanced LIGO in their lab experiments. The greater the laser power and the lighter the mass of the mirror oscillator, the stronger the radiation pressure-driven motion. To be able to detect this motion with less laser power, they needed to create an extremely low-mass mirror oscillator. They scaled down the 40-kilogram mirrors of Advanced LIGO with a 100-nanogram mirror oscillator (less than the mass of a grain of salt).</p> <p>The team also faced the significant challenge of designing a mirror oscillator that could exhibit quantum behavior at room temperature. Previously, observing quantum effects like QRPN required cryogenic cooling so that the motion due to heat energy of the oscillator would not mask the QRPN. In addition to being challenging and impractical, vibrations associated with cryogenic cooling interferes with LIGO’s operation, so conducting experiments at room temperature would be more readily applicable to LIGO itself. After many iterations of design and testing, Mavalvala and her MIT colleagues designed a mirror oscillator that allowed the team to reach a low enough level of thermally driven fluctuations that the mirror motion was dominated by QRPN at room temperature — the first-ever study to do so.</p> <p>“It’s really pretty mind-boggling that we can observe this room-temperature, macroscopic object — you can see it with the naked eye if you squint enough — being pushed around by quantum fluctuations,” Mavalvala says. “Its thermal jitter is small enough that it’s being tickled ever-so-slightly by quantum fluctuations, and we can measure that.”</p> <p>This was also the first study to detect QRPN at frequencies relevant to gravitational wave detectors. Their success means that they can now design additional experiments that reflect the radiation pressure conditions in Advanced LIGO itself.</p> <p>“This experiment mimics an important noise source in Advanced LIGO,” says Mavalvala. “It's now a test bed where we can try out new ideas for improving Advanced LIGO without impinging on the instrument’s own operating time.”</p> <p>Advanced LIGO does not yet run its lasers at strong enough power for QRPN to be a limiting factor in gravitational wave detections. But, as the instruments become more sensitive, this type of noise will soon become a problem and limit Advanced LIGO’s capabilities. When Mavalvala and her collaborators recognized QRPN as an imminent issue, they strove to recreate its effects in the laboratory so that they can start exploring ways to overcome this challenge.</p> <p>“We've known for a long time that this QRPN would be a limitation for Advanced LIGO,” says Mavalvala. “Now that we are able to reproduce that effect in a laboratory setting, we can start to test ideas for how to improve that limit.”</p> <p>Mavalvala’s primary collaborator at LSU was Thomas Corbitt, an associate professor of physics and astronomy. Corbitt was formerly a graduate student and post-doctoral scholar in Mavalvala’s lab at MIT. They have since collaborated for many years.</p> <p>“This is the first time this effect has been observed in a system similar to gravitational wave interferometers and in LIGO’s frequency band,” says Corbitt. “While this work was motivated by the imperative to make ever-more-sensitive gravitational wave detectors, it is of wide interest.”</p> <p><strong>New directions</strong></p> <p>Since the original detection of a binary black hole merger in 2015, LIGO has also captured signals from collisions of neutron stars, as well as additional black hole collisions. These waves ripple outward from interactions that can take place more than a billion light years away. While LIGO’s capabilities are impressive, Mavalvala and her team plan to continue finding ways to make LIGO even more powerful.</p> <p>Before they collide, black holes, for example, orbit each other slowly and at lower frequencies. As the two black holes get closer, their orbits speed up and they swirl around each other at high speeds and high frequencies. If Advanced LIGO becomes sensitive enough to pick up lower frequencies, Mavalvala says we may someday detect these systems earlier in the process, before the pair collides, allowing us to draw an ever-clearer picture of these distant spacetime phenomena. She and her team aim to make sure that factors such as QRPN don’t limit Advanced LIGO’s growing power.</p> <p>“At this moment in time, Advanced LIGO is the best it can be at its job: to look out at the sky and detect gravitational wave events,” says Mavalvala. “In parallel, we have all of these ideas for making it better, and we have to be able to try those out in laboratories. This measurement allows that to happen with QRPN for the first time.”</p> New technology allows LIGO researchers to model noise from quantum phenomena at room temperature. The green path shows the optical fiber that carries light into the chamber, and the red path shows where the light exits.Physics, Astrophysics, Black holes, Gravity, Neutron Stars, Space, astronomy and planetary science, Research, School of Science, Kavli Institute TESS discovers its first Earth-sized planet Orbiting a nearby star, the new planet is the smallest identified so far by the TESS mission. Tue, 16 Apr 2019 00:00:00 -0400 Jennifer Chu | MIT News Office <p>NASA’s Transiting Exoplanet Survey Satellite, TESS, has discovered its first Earth-sized exoplanet. The planet, named HD 21749c, is the smallest world outside our solar system that TESS has identified yet.</p> <p>In a paper published today in the journal <em>Astrophysical Journal Letters</em>, an MIT-led team of astronomers reports that the new planet orbits the star HD 21749 — a very nearby star, just 52 light years from Earth. The star also hosts a second planet — HD 21749b — a warm “sub-Neptune” with a longer, 36-day orbit, which the team <a href="">reported</a> previously and now details further in the current paper.</p> <p>The new Earth-sized planet is likely a rocky though uninhabitable world, as it circles its star in just 7.8 days — a relatively tight orbit that would generate surface temperatures on the planet of up to 800 degrees Fahrenheit.</p> <p>The discovery of this Earth-sized world is nevertheless exciting, as it demonstrates TESS’ ability to pick out small planets around nearby stars. In the near future, the TESS team expects the probe should reveal even colder planets, with conditions more suitable for hosting life.</p> <p>“For stars that are very close by and very bright, we expected to find up to a couple dozen Earth-sized planets,” says lead author and TESS member Diana Dragomir, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “And here we are — this would be our first one, and it’s a milestone for TESS. It sets the path for finding smaller planets around even smaller stars, and those planets may potentially be habitable.”</p> <p>TESS has been hunting for planets beyond our solar system since it launched on April 18, 2018. The satellite is a NASA Astrophysics Explorer mission that is led and operated by MIT, and is designed to observe nearly the entire sky, in overlapping, month-long patches, or “sectors,” as it orbits the Earth. As it circles our own planet, TESS focuses its four cameras outward to monitor the nearest, brightest stars in the sky, looking for any periodic dips in starlight that could indicate the presence of an exoplanet as it passes in front of its host star.</p> <p>Over its two-year mission, TESS aims to identify for the astronomy community at least 50 small, rocky planets, along with estimates of their masses. To date, the mission has discovered 10 planets smaller than Neptune, four of their masses which have been estimated, including π Men b, a planet twice the size of Earth, with a six-day orbit around its star; LHS 3844b, a hot, rocky world that’s slightly bigger than Earth and circles its star in a blistering 11 hours; and TOI 125b and c — two “sub-Neptunes” that orbit the same star, both within about a week. All four of these planets were identified from data obtained during TESS’ first two observing sectors — a good indication, the team writes in its paper, that “many more are to be found.” &nbsp;</p> <p>Dragomir picked out this newest, Earth-sized planet from the first four sectors of TESS observations. When these data became available, in the form of light curves, or intensities of starlight, she fed them into a software code to look for interesting, periodic signals. The code first identified a possible transit that the team later confirmed as the warm sub-Neptune they announced earlier this year.</p> <p>As is usually the case with small planets, where there’s one, there are likely to be more, and Dragomir and her colleagues decided to comb through the same observations again to see if they could spot any other small worlds hiding in the data. &nbsp;</p> <p>“We know these planets often come in families,” Dragomir says. “So we searched all the data again, and this small signal came up.”</p> <p>The team identified a small dip in the light from HD 21749, that occurred every 7.8 days. Ultimately, the researchers identified 11 such periodic dips, or transits, and determined that the star’s light was being momentarily blocked by a planet about the size of the Earth.</p> <p>While this is the first Earth-sized planet discovered by TESS, other Earth-sized exoplanets have been discovered in the past, mainly by NASA’s Kepler Space Telescope, a since-retired telescope that monitored more than 530,000 stars. In the end, the Kepler mission detected 2,662 planets, many of which were Earth-sized, and a handful of those were deemed to be within their star’s habitable zone — where a balance of conditions could be suitable for hosting life.</p> <p>However, Kepler observed stars that are many leagues further away than those that are monitored by TESS. Therefore, Dragomir says that following up on any of Kepler’s far-flung, Earth-sized planets would be much harder than studying planets orbiting TESS’ much closer, brighter stars.</p> <p>“Because TESS monitors stars that are much closer and brighter, we can measure the mass of this planet in the very near future, whereas for Kepler’s Earth-sized planets, that was out of the question,” Dragomir says. “So this new TESS discovery could lead to the first mass measurement of an Earth-sized planet. And we’re excited about what that mass could be. Will it be Earth’s mass? Or heavier? We don’t really know.”</p> NASA's Transiting Exoplanet Survey Satellite (TESS), shown here in a conceptual illustration, will identify exoplanets orbiting the brightest stars just outside our solar system.Image: NASA's Goddard Space Flight CenterAeronautical and astronautical engineering, Astronomy, Astrophysics, EAPS, Exoplanets, Kavli Institute, NASA, Planetary science, Research, Satellites, School of Science, space, Space, astronomy and planetary science Astronomers capture first image of a black hole ESO, ALMA, and APEX contribute to paradigm-shifting observations of the gargantuan black hole at the heart of the galaxy Messier 87. (Press release) Wed, 10 Apr 2019 09:03:25 -0400 MIT News Office <p><em>The following press release was issued today by the European Southern Observatory.</em></p> <p>This breakthrough was announced today in a series of six papers published in a special issue of &nbsp;The Astrophysical Journal Letters. The image reveals the black hole at the centre of Messier 87 [1], a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides 55 million light-years from Earth and has a mass 6.5 billion times that of the Sun [2].</p> <p>The EHT links telescopes around the globe to form an unprecedented Earth-sized virtual telescope [3]. The EHT offers scientists a new way to study the most extreme objects in the Universe predicted by Einstein’s general relativity during the centenary year of the historic experiment that first confirmed the theory [4].</p> <p>"We have taken the first picture of a black hole," said EHT project director Sheperd S. Doeleman of the Center for Astrophysics | Harvard &amp; Smithsonian. "This is an extraordinary scientific feat accomplished by a team of more than 200 researchers."</p> <p>Black holes are extraordinary cosmic objects with enormous masses but extremely compact sizes. The presence of these objects affects their environment in extreme ways, warping spacetime and superheating any surrounding material.</p> <p>"If immersed in a bright region, like a disc of glowing gas, we expect a black hole to create a dark region similar to a shadow — something predicted by Einstein’s general relativity that we’ve never seen before," explained chair of the EHT Science Council Heino Falcke of Radboud University, the Netherlands. "This shadow, caused by the gravitational bending and capture of light by the event horizon, reveals a lot about the nature of these fascinating objects and has allowed us to measure the enormous mass of M87’s black hole."<br /> Multiple calibration and imaging methods have revealed a ring-like structure with a dark central region — the black hole’s shadow — that persisted over multiple independent EHT observations.</p> <p>"Once we were sure we had imaged the shadow, we could compare our observations to extensive computer models that include the physics of warped space, superheated matter and strong magnetic fields. Many of the features of the observed image match our theoretical understanding surprisingly well," remarks Paul T.P. Ho, EHT Board member and Director of the East Asian Observatory [5]. "This makes us confident about the interpretation of our observations, including our estimation of the black hole’s mass."</p> <p>"The confrontation of theory with observations is always a dramatic moment for a theorist. It was a relief and a source of pride to realise that the observations matched our predictions so well," elaborated EHT Board member Luciano Rezzolla of Goethe Universität, Germany.</p> <p>Creating the EHT was a formidable challenge which required upgrading and connecting a worldwide network of eight pre-existing telescopes deployed at a variety of challenging high-altitude sites. These locations included volcanoes in Hawai`i and Mexico, mountains in Arizona and the Spanish Sierra Nevada, the Chilean Atacama Desert, and Antarctica.</p> <p>The EHT observations use a technique called very-long-baseline interferometry (VLBI) which synchronises telescope facilities around the world and exploits the rotation of our planet to form one huge, Earth-size telescope observing at a wavelength of 1.3mm. VLBI allows the EHT to achieve an angular resolution of 20 micro-arcseconds — enough to read a newspaper in New York from a café in Paris [6].</p> <p>The telescopes contributing to this result were ALMA, APEX, the IRAM 30-meter telescope, the James Clerk Maxwell Telescope, the Large Millimeter Telescope Alfonso Serrano, the Submillimeter Array, the Submillimeter Telescope, and the South Pole Telescope [7]. Petabytes of raw data from the telescopes were combined by highly specialised supercomputers hosted by the Max Planck Institute for Radio Astronomy and MIT Haystack Observatory.</p> <p>European facilities and funding played a crucial role in this worldwide effort, with the participation of advanced European telescopes and the support from the European Research Council — particularly a €14 million grant for the BlackHoleCam project [8]. Support from ESO, IRAM and the Max Planck Society was also key. "This result builds on decades of European expertise in millimetre astronomy”, commented Karl Schuster, Director of IRAM and member of the EHT Board.</p> <p>The construction of the EHT and the observations announced today represent the culmination of decades of observational, technical, and theoretical work. This example of global teamwork required close collaboration by researchers from around the world. Thirteen partner institutions worked together to create the EHT, using both pre-existing infrastructure and support from a variety of agencies. Key funding was provided by the US National Science Foundation (NSF), the EU's European Research Council (ERC), and funding agencies in East Asia.</p> <p>“ESO is delighted to have significantly contributed to this result through its European leadership and pivotal role in two of the EHT’s component telescopes, located in Chile — ALMA and APEX,” commented ESO Director General Xavier Barcons. “ALMA is the most sensitive facility in the EHT, and its 66 high-precision antennas were critical in making the EHT a success.”</p> <p>"We have achieved something presumed to be impossible just a generation ago," concluded Doeleman. "Breakthroughs in technology, connections between the world's best radio observatories, and innovative algorithms all came together to open an entirely new window on black holes and the event horizon.”</p> <p><strong>Notes</strong></p> <p>[1] The shadow of a black hole is the closest we can come to an image of the black hole itself, a completely dark object from which light cannot escape. The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across.</p> <p>[2] Supermassive black holes are relatively tiny astronomical objects — which has made them impossible to directly observe until now. As the size of a black hole’s event horizon is proportional to its mass, the more massive a black hole, the larger the shadow. Thanks to its enormous mass and relative proximity, M87’s black hole was predicted to be one of the largest viewable from Earth — making it a perfect target for the EHT.</p> <p>[3] Although the telescopes are not physically connected, they are able to synchronize their recorded data with atomic clocks — hydrogen masers — which precisely time their observations. These observations were collected at a wavelength of 1.3 mm during a 2017 global campaign. Each telescope of the EHT produced enormous amounts of data – roughly 350 terabytes per day – which was stored on high-performance helium-filled hard drives. These data were flown to highly specialised supercomputers — known as correlators — at the Max Planck Institute for Radio Astronomy and MIT Haystack Observatory to be combined. They were then painstakingly converted into an image using novel computational tools developed by the collaboration.</p> <p>[4] 100 years ago, two expeditions set out for Principe Island off the coast of Africa and Sobral in Brazil to observe the 1919 solar eclipse, with the goal of testing general relativity by seeing if starlight would be bent around the limb of the sun, as predicted by Einstein. In an echo of those observations, the EHT has sent team members to some of the world's highest and most isolated radio facilities to once again test our understanding of gravity.</p> <p>[5] The East Asian Observatory (EAO) partner on the EHT project represents the participation of many regions in Asia, including China, Japan, Korea, Taiwan, Vietnam, Thailand, Malaysia, India and Indonesia.</p> <p>[6] Future EHT observations will see substantially increased sensitivity with the participation of the IRAM NOEMA Observatory, the Greenland Telescope and the Kitt Peak Telescope.</p> <p>[7] ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), the U.S. National Science Foundation (NSF), and the National Institutes of Natural Sciences(NINS) of Japan, together with the National Research Council (Canada), the Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. APEX is operated by ESO, the 30-meter telescope is operated by IRAM (the IRAM Partner Organizations are MPG (Germany), CNRS (France) and IGN (Spain)), the James Clerk Maxwell Telescope is operated by the EAO, the Large Millimeter Telescope Alfonso Serrano is operated by INAOE and UMass, the Submillimeter Array is operated by SAO and ASIAA and the Submillimeter Telescope is operated by the Arizona Radio Observatory (ARO). The South Pole Telescope is operated by the University of Chicago with specialized EHT instrumentation provided by the University of Arizona.</p> <p>[8] BlackHoleCam is an EU-funded project to image, measure and understand astrophysical black holes. The main goal of BlackHoleCam and the Event Horizon Telescope (EHT) is to make the first ever images of the billion solar masses black hole in the nearby galaxy M87 and of its smaller cousin, Sagittarius A*, the supermassive black hole at the centre of our Milky Way. This allows the determination of the deformation of spacetime caused by a black hole with extreme precision.<br /> &nbsp;<br /> <strong>More information</strong></p> <p>This research was presented in a series of six papers published today in a special issue of The Astrophysical Journal Letters.</p> <p>The EHT collaboration involves more than 200 researchers from Africa, Asia, Europe, North and South America. The international collaboration is working to capture the most detailed black hole images ever by creating a virtual Earth-sized telescope. Supported by considerable international investment, the EHT links existing telescopes using novel systems — creating a fundamentally new instrument with the highest angular resolving power that has yet been achieved.<br /> The individual telescopes involved are; ALMA, APEX, the IRAM 30-meter Telescope, the IRAM NOEMA Observatory, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope (LMT), the Submillimeter Array (SMA), the Submillimeter Telescope (SMT), the South Pole Telescope (SPT), the Kitt Peak Telescope, and the Greenland Telescope (GLT).</p> <p>The EHT consortium consists of 13 stakeholder institutes; the Academia Sinica Institute of Astronomy and Astrophysics, the University of Arizona, the University of Chicago, the East Asian Observatory, Goethe-Universitaet Frankfurt, Institut de Radioastronomie Millimétrique, Large Millimeter Telescope, Max Planck Institute for Radio Astronomy, MIT Haystack Observatory, National Astronomical Observatory of Japan, Perimeter Institute for Theoretical Physics, Radboud University and the Smithsonian Astrophysical Observatory. &nbsp;</p> <p>ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky.”</p> The Event Horizon Telescope (EHT) is a global network of radio telescopes that work together as one virtual, Earth-sized telescope, with a resolution sharp enough to “see” a black hole’s shadow. Image: ESO/ L. CalçadaAstronomy, Astrophysics, Black holes, Haystack Observatory, National Science Foundation (NSF), Research, space, Space, astronomy and planetary science Working together as a “virtual telescope,” observatories around the world produce first direct images of a black hole Images reveal supermassive black hole at the heart of the Messier 87 galaxy. Wed, 10 Apr 2019 09:00:24 -0400 Jennifer Chu | MIT News Office <p>An international team of over 200 astronomers, including scientists from MIT’s Haystack Observatory, has captured the first direct images of a black hole. They accomplished this remarkable feat by coordinating the power of eight major radio observatories on four continents, to work together as a virtual, Earth-sized telescope.</p> <p>In a series of papers published today in a special issue of <em>Astrophysical Journal Letters</em>, the team has revealed four images of the supermassive black hole at the heart of Messier 87, or M87, a galaxy within the Virgo galaxy cluster, 55 million light years from Earth.</p> <p>All four images show a central dark region surrounded by a ring of light that appears lopsided — brighter on one side than the other.</p> <p>Albert Einstein, in his theory of general relativity, predicted the existence of black holes, in the form of infinitely dense, compact regions in space, where gravity is so extreme that nothing, not even light, can escape from within. By definition, black holes are invisible. But if a black hole is surrounded by light-emitting material such as plasma, Einstein’s equations predict that some of this material should create a “shadow,” or an outline of the black hole and its boundary, also known as its event horizon.</p> <p>Based on the new images of M87, the scientists believe they are seeing a black hole’s shadow for the first time, in the form of the dark region at the center of each image.</p> <p>Relativity predicts that the immense gravitational field will cause light to bend around the black hole, forming a bright ring around its silhouette, and will also cause the surrounding material to orbit around the object at close to light speed. The bright, lopsided ring in the new images offers visual confirmation of these effects: The material headed toward our vantage point as it rotates around appears brighter than the other side.</p> <p>From these images, theorists and modelers on the team have determined that the black hole is about 6.5 billion times as massive as our sun. Slight differences between each of the four images suggest that material is zipping around the black hole at lightning speed.</p> <p>“This black hole is much bigger than the orbit of Neptune, and Neptune takes 200 years to go around the sun,” says Geoffrey Crew, a research scientist at Haystack Observatory. “With the M87 black hole being so massive, an orbiting planet would go around it within a week and be traveling at close to the speed of light.”</p> <p>“People tend to view the sky as something static, that things don’t change in the heavens, or if they do, it’s on timescales that are longer than a human lifetime,” says Vincent Fish, a research scientist at Haystack Observatory. “But what we find for M87 is, at the very fine detail we have, objects change on the timescale of days. In the future, we can perhaps produce movies of these sources. Today we’re seeing the starting frames.”</p> <p>“These remarkable new images of the M87 black hole prove that Einstein was right yet again,” says Maria Zuber, MIT’s vice president for research and the E.A. Griswold Professor of Geophysics in the Department of Earth, Atmospheric and Planetary Sciences. “The discovery was enabled by advances in digital systems at which Haystack engineers&nbsp;have long excelled.”</p> <p><strong>“Nature was kind”</strong></p> <p>The images were taken by the Event Horizon Telescope, or EHT, a planet-scale array comprising eight radio telescopes, each in a remote, high-altitude environment, including the mountaintops of Hawaii, Spain’s Sierra Nevada, the Chilean desert, and the Antarctic ice sheet.</p> <p>On any given day, each telescope operates independently, observing astrophysical objects that emit faint radio waves. However, a black hole is infinitely smaller and darker than any other radio source in the sky. To see it clearly, astronomers need to use very short wavelengths — in this case, 1.3 millimeters — that can cut through the clouds of material between a black hole and the Earth.</p> <p>Making a picture of a black hole also requires a magnification, or “angular resolution,” equivalent to reading a text on a phone in New York from a sidewalk café in Paris. A telescope’s angular resolution increases with the size of its receiving dish. However, even the largest radio telescopes on Earth are nowhere near big enough to see a black hole.</p> <p>But when multiple radio telescopes, separated by very large distances, are synchronized and focused on a single source in the sky, they can operate as one very large radio dish, through a technique known as very long baseline interferometry, or VLBI. Their combined angular resolution as a result can be vastly improved.</p> <p>For EHT, the eight participating telescopes summed up to a virtual radio dish as big as the Earth, with the ability to resolve an object down to 20 micro-arcseconds — about 3 million times sharper than 20/20 vision. By a happy coincidence, that’s about the precision required to view a black hole, according to Einstein’s equations.</p> <p>“Nature was kind to us, and gave us something just big enough to see by using state-of-the-art equipment and techniques,” says Crew, co-leader of the EHT correlation working group and the ALMA Observatory VLBI team.</p> <p><strong>“Gobs of data”</strong></p> <p>On April 5, 2017, the EHT began observing M87. After consulting numerous weather forecasts, astronomers identified four nights that would produce clear conditions for all eight observatories — a rare opportunity, during which they could work as one collective dish to observe the black hole.</p> <p>In radio astronomy, telescopes detect radio waves, at frequencies that register incoming photons as a wave, with an amplitude and phase that’s measured as a voltage. As they observed M87, every telescope took in streams of data in the form of voltages, represented as digital numbers.</p> <p>“We’re recording gobs of data — petabytes of data for each station,” Crew says.</p> <p>In total, each telescope took in about one petabyte of data, equal to 1 million gigabytes. Each station recorded this enormous influx that onto several Mark6 units — ultrafast data recorders that were originally developed at Haystack Observatory.</p> <p>After the observing run ended, researchers at each station packed up the stack of hard drives and flew them via FedEx to Haystack Observatory, in Massachusetts, and Max Planck Institute for Radio Astronomy, in Germany. (Air transport was much faster than transmitting the data electronically.) At both locations, the data were played back into a highly specialized supercomputer called a correlator, which processed the data two streams at a time.</p> <p>As each telescope occupies a different location on the EHT’s virtual radio dish, it has a slightly different view of the object of interest — in this case, M87. The data received by two separate telescopes may encode a similar signal of the black hole but also contain noise that’s specific to the respective telescopes.</p> <p>The correlator lines up data from every possible pair of the EHT’s eight telescopes. From these comparisons, it mathematically weeds out the noise and picks out the black hole’s signal. High-precision atomic clocks installed at every telescope time-stamp incoming data, enabling analysts to match up data streams after the fact.</p> <p>“Precisely lining up the data streams and accounting for all kinds of subtle perturbations to the timing is one of the things that Haystack specializes in,” says Colin Lonsdale, Haystack director and vice chair of the EHT directing board.</p> <p>Teams at both Haystack and Max Planck then began the painstaking process of “correlating” the data, identifying a range of problems at the different telescopes, fixing them, and rerunning the correlation, until the data could be rigorously verified. Only then were the data released to four separate teams around the world, each tasked with generating an image from the data using independent techniques.</p> <p>“It was the second week of June, and I remember I didn’t sleep the night before the data was released, to be sure I was prepared,” says Kazunori Akiyama, co-leader of the EHT imaging group and a postdoc working at Haystack.</p> <p>All four imaging teams previously tested their algorithms on other astrophysical objects, making sure that their techniques would produce an accurate visual representation of the radio data. When the files were released, Akiyama and his colleagues immediately ran the data through their respective algorithms. Importantly, each team did so independently of the others, to avoid any group bias in the results.</p> <p>“The first image our group produced was slightly messy, but we saw this ring-like emission, and I was so excited at that moment,” Akiyama remembers. “But simultaneously I was worried that maybe I was the only person getting that black hole image.”</p> <p>His concern was short-lived. Soon afterward all four teams met at the Black Hole Initiative at Harvard University to compare images, and found, with some relief, and much cheering and applause, that they all produced the same, lopsided, ring-like structure — the first direct images of a black hole.</p> <p>“There have been ways to find signatures of black holes in astronomy, but this is the first time anyone’s ever taken a picture of one,” Crew says. “This is a watershed moment.”</p> <p><strong>“A new era”</strong></p> <p>The idea for the EHT was conceived in the early 2000s by Sheperd Doeleman PhD ’95, who was leading a pioneering VLBI program at Haystack Observatory and now directs the EHT project as an astronomer at the Harvard-Smithsonian Center for Astrophysics. At the time, Haystack engineers were developing the digital back-ends, recorders, and correlator that could process the enormous datastreams that an array of disparate telescopes would receive.</p> <p>“The concept of imaging a black hole has been around for decades,” Lonsdale says. “But it was really the development of modern digital systems that got people thinking about radio astronomy as a way of actually doing it. More telescopes on mountaintops were being built, and the realization gradually came along that, hey, [imaging a black hole] isn’t absolutely crazy.”</p> <p>In 2007, Doeleman’s team put the EHT concept to the test, installing Haystack’s recorders on three widely scattered radio telescopes and aiming them together at Sagittarius A*, the black hole at the center of our own galaxy.</p> <p>“We didn’t have enough dishes to make an image,” recalls Fish, co-leader of the EHT science operations working group. “But we could see there was something there that’s about the right size.”</p> <p>Today, the EHT has grown to an array of 11 observatories: ALMA, APEX, the Greenland Telescope, the IRAM 30-meter Telescope, the IRAM NOEMA Observatory, the Kitt Peak Telescope, the James Clerk Maxwell Telescope, the Large Millimeter Telescope Alfonso Serrano, the Submillimeter Array, the Submillimeter Telescope, and the South Pole Telescope. (Read further in the related <a href="">press release</a>.)</p> <p>Coordinating observations and analysis has involved over 200 scientists from around the world who make up the <a href="">EHT collaboration</a>, with 13 main institutions, including Haystack Observatory.&nbsp;Key funding was provided by the National Science Foundation, the European Research Council, and funding agencies in East Asia, including the Japan Society for the Promotion of Science. The telescopes contributing to this result were&nbsp;ALMA,&nbsp;APEX, the&nbsp;IRAM 30-meter telescope, the&nbsp;James Clerk Maxwell Telescope, the&nbsp;Large Millimeter Telescope Alfonso Serrano, the&nbsp;Submillimeter Array, the&nbsp;Submillimeter Telescope, and the&nbsp;South Pole Telescope.</p> <p>More observatories are scheduled to join the EHT array, to sharpen the image of M87 as well as attempt to see through the dense material that lies between Earth and the center of our own galaxy, to the heart of Sagittarius A*.</p> <p>“We’ve demonstrated that the EHT is the observatory to see a black hole on an event horizon scale,” Akiyama says. “This is the dawn of a new era of black hole astrophysics.”</p> <p>The Haystack EHT team includes John Barrett, Roger Cappallo, Joseph Crowley, Mark Derome, Kevin Dudevoir, Michael Hecht, Lynn Matthews, Kotaro Moriyama, Michael Poirier, Alan Rogers, Chester Ruszczyk, Jason SooHoo, Don Sousa, Michael Titus, and Alan Whitney. Additional contributors were MIT alumni Daniel Palumbo, Katie Bouman, Lindy Blackburn, Sera Markoff, and Bill Freeman, a professor in MIT’s Department of Electrical Engineering and Computer Science.</p> The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. In coordinated press conferences across the globe, EHT researchers revealed that they succeeded, unveiling the first direct visual evidence of the supermassive black hole in the center of Messier 87 and its shadow.Credit: EHT CollaborationAstronomy, Astrophysics, Black holes, Haystack Observatory, National Science Foundation (NSF), Research, Space, astronomy and planetary science School of Science announces 2019 Infinite Mile Awards Ten staff members in the School of Science are recognized for going above and beyond their job descriptions to support a better Institute. Tue, 02 Apr 2019 10:12:01 -0400 School of Science <p>The MIT <a href="">School of Science</a> has announced the winners of the 2019 Infinite Mile Award, which is presented annually to staff members within the school who demonstrate exemplary dedication to making MIT a better place.</p> <p>Nominated by their colleagues, these winners are notable for their unrelenting and extraordinary hard work in their positions, which can include mentoring fellow community members, innovating new solutions to problems big and small, building their communities, or going far above and beyond their job descriptions to support the goals of their home departments, labs, and research centers.</p> <p>The 2019 Infinite Mile Award winners are:</p> <p>Christine Brooks, an administrative assistant in the <a href="">Department of Chemistry</a>, nominated by Mircea Dincă and several members of the Dincă, Schrock, and Cummins groups;</p> <p>Annie Cardinaux, a research specialist in the <a href="">Department of Brain and Cognitive Sciences</a>, nominated by Pawan Sinha;</p> <p>Kimberli DeMayo, a human resources consultant in the <a href="">Department of Mathematics</a>, nominated by Nan Lin, Dennis Porche, and Paul Seidel, with support from several other faculty members;</p> <p>Arek Hamalian, a technical associate at the <a href="">Picower Institute for Learning and Memory</a>, nominated by Susumu Tonegawa;</p> <p>Jonathan Harmon, an administrative assistant in the <a href="">Department of Mathematics</a>, nominated by Pavel Etingof and Kimberli DeMayo, with support from several other faculty members;</p> <p>Tanya Khovanova, a lecturer in the <a href="">Department of Mathematics</a>, nominated by Pavel Etingof, David Jerison, and Slava Gerovitch;</p> <p>Kelley Mahoney, an SRS financial staff member in the <a href="">Kavli Institute for Astrophysics and Space Research</a>, nominated by Sarah Brady, Michael McDonald, Anna Frebel, Jacqueline Hewitt, Jack Defandorf, and Stacey Sullaway;</p> <p>Walter Massefski, the director of instrumentation facility in the <a href="">Department of Chemistry</a>, nominated by Timothy Jamison and Richard Wilk;</p> <p>Raleigh McElvery, a communications coordinator in the <a href="">Department of Biology</a>, nominated by Vivian Siegel with support from Amy Keating, Julia Keller, and Erika Reinfeld; and</p> <p>Kate White, an administrative officer in the <a href="">Department of Brain and Cognitive Sciences</a>, nominated by Jim DiCarlo, Michale Fee, Sara Cody-Larnard, Rachel Donahue, Federico Chiavazza, Matthew Regan, Gayle Lutchen, and William Lawson.</p> <p>The recipients will receive a monetary award in addition to being honored at a celebratory reception, along with their peers, family and friends, and the recipients of the 2019 Infinite Kilometer Award this month.</p> School of Science, Chemistry, Brain and cognitive sciences, Mathematics, Picower Institute for Learning and Memory, Kavli Institute, Biology, Staff, Awards, honors and fellowships, Community 3 Questions: Lisa Barsotti on the new and improved LIGO “If we are very lucky, we might observe something new … or maybe even something totally unexpected.” Mon, 01 Apr 2019 00:00:00 -0400 Jennifer Chu | MIT News Office <p><em>The search for infinitely faint ripples in space-time is back in full swing. Today, LIGO, the Laser Interferometer Gravitational-wave Observatory, operated jointly by Caltech and MIT, resumes its hunt for gravitational waves and the immense cosmic phenomena from which they emanate. </em></p> <p><em>Over the past several months, LIGO’s twin detectors, in Washington and Lousiana, have been offline, undergoing upgrades to their lasers, mirrors, and other components, which will enable the detectors to listen for gravitational waves over a far greater range, out to about 550 million light-years away — around 190 million light-years farther out than before. </em></p> <p><em>As the LIGO detectors turn back on, they will be joined by Virgo, the European-based counterpart based in Italy, which also turns on today after undergoing upgrades that doubled its sensitivity. With both LIGO and Virgo back online, scientists anticipate that detections of gravitational waves from the farthest reaches of the universe may be a regular occurrence. </em></p> <p>MIT News<em> spoke with LIGO member Lisa Barsotti, principal research scientist at MIT’s Kavli Institute for Astrophysics and Space Research, about the potential discoveries that lie ahead. </em></p> <p><strong>Q: </strong>Give us a sense of the new capabilities that the LIGO detectors now have. What sort of upgrades were made?</p> <p><strong>A: </strong>Both LIGO detectors are coming back online more sensitive than ever before, thanks to a wide range of improvements. In particular, we more than doubled the laser power in the interferometers to reduce one of the LIGO fundamental noise sources — quantum "shot noise,” caused by the uncertainty of the arrival time of photons onto the main photodetector. We also deployed a new technology, "squeezed" light, that uses quantum optics to further reduce shot noise.</p> <p>Combined with other upgrades to mitigate technical noises (for example noises introduced by the control scheme or from stray light) we improved the sensitivity to binary neutron stars by 40 percent in each detector, with respect to the past observing run.</p> <p><strong>Q: </strong>What do these new capabilities mean for you, as a researcher who will be looking through the data from these upgraded detectors?</p> <p><strong>A: </strong>I am personally very excited to see the LIGO detectors operating with squeezed light! This new technology has been developed here at MIT after many years of research to make it compatible with the very stringent LIGO requirements, and our graduate students have been leading the commissioning of this new system at the observatories. It is particularly rewarding to see that we succeeded in making LIGO better.</p> <p>Also, operation at high laser power has been enabled by another upgrade developed and built here at MIT — an "acoustic mode damper" glued to the main LIGO optics that mitigates instabilities originating with high laser power. We are looking forward to seeing many years of work in our labs pay off in this observing run!</p> <p><strong>Q: </strong>What new phenomena are you hoping to detect, and how soon could you detect them, with these new capabilities?</p> <p><strong>A: </strong>We hope to detect more binary neutron star systems (so far only one has been detected), and thanks to the improved LIGO sensitivity, we should be able to observe them with high signal-to-noise ratio. And more black holes, obviously! The more sources we detect, the more we can learn about the way these systems form and evolve.</p> <p>If we are very lucky, we might observe something new, like a neutron star-black hole system, or maybe even something totally unexpected.&nbsp;Not only are the LIGO detectors better than before — the Virgo detector in Italy more than doubled its sensitivity with respect to the last observing run, and this will improve our ability to localize sources in the sky, facilitating the follow-up of telescopes at multiple wavelengths. So, if the last observing run, “O2,” will be remembered as the one that started multimessenger astronomy, I hope the upcoming one, “O3,” will be the one in which multimessenger astronomy becomes the new normal!</p> LIGO laboratory detection site near Hanford in eastern Washington.Image: Caltech/MIT/LIGO LaboratoryAstronomy, Astrophysics, Black holes, Kavli Institute, LIGO, National Science Foundation (NSF), Physics, Research, School of Science, 3 Questions Lighting up exoplanets The Heising-Simons Foundation selects Clara Sousa-Silva and Benjamin Rackham for 51 Pegasi b Fellowships at MIT. Wed, 27 Mar 2019 13:00:00 -0400 Lauren Hinkel | EAPS <p>Ever since the discovery of the first exoplanet, 51 Pegasi b, hidden within the well-known Pegasus constellation in 1995, the burgeoning field of exoplanetary astronomy has taken off. Since then, the field has seen an explosion of related scientific specialties, and scientists have been able to detect more than 3,500 worlds beyond our solar system.&nbsp;People had always dreamed about the secrets other worlds held,&nbsp;now researchers empowered by advances in technology&nbsp;are able to find and study them.</p> <p>As the <a href="" target="_self">50th anniversary</a> of the first Apollo moon landing approaches, excitement about planetary bodies has been heightened. The growing field of planetary astronomy studies celestial objects both within and beyond our solar system, bridging planetary science and astronomy.</p> <p>This year, the Heising-Simons Foundation has granted <a href="" target="_blank">six researchers</a> from around the U.S. 51 Pegasi b fellowships to support the search for this knowledge, and two of those six will conduct their studies at MIT. Clara Sousa-Silva and Benjamin Rackham were selected as some of the most promising astronomers to pursue “innovative independent research ideas, take risks, and tackle challenging questions what will accelerate the field.” They will be conducting their work within MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS).</p> <p><strong>Hosting life</strong></p> <p>“I want to study every molecule on every possible exoplanet atmosphere, and then try to recognize under what conditions certain molecules can signify life,”&nbsp;Sousa-Silva says.</p> <p>Sousa-Silva is a quantum astrochemist and an EAPS postdoc with a desire to understand the mechanisms of the universe, particularly exoplanet habitability — with a focus on the molecules that compose their atmospheres. As a theorist, Sousa-Silva simulates the ways individual molecules interact with light so that they can be identified anywhere in the galaxy. She combines quantum physics and computer calculations to create molecular “fingerprints” that allow scientists to detect remote gases on exoplanet atmospheres, in particular gases that are associated with life.</p> <p>Sousa-Silva is currently examining molecules that are associated with anaerobic biology in order to detect life on planets without oxygen. Her work has culminated in a new method, Rapid Approximate Spectral Calculations for ALL (RASCALL), that generates simulations of molecules. RASCALL can help scientists make rapid decisions about whether to follow up promising observational data with more detailed study.</p> <p>“What excites me most is the idea of combining supremely fundamental science with really inspirational, out-of-this-world questions about what life looks like elsewhere,” says Sousa-Silva.</p> <p>During her fellowship, Sousa-Silva will expand her publicly available database of spectra to ultimately include sixteen thousand molecules, and use those data to completely and accurately interpret exoplanet atmospheres. With these, she’ll be able to rank promising biosignatures by their spectroscopic potential, not limited to Earth-like molecules. The goal is to have the tools to identify any given alien biosphere. She points out that, not only is molecular behavior a fundamental and universal truth, and as such worth knowing, but understanding which molecules are on an exoplanet, and their role within it, is the most promising avenue for detecting life in the galaxy.</p> <p>To understand the role of molecules in space, Sousa-Silva’s research will straddle astronomy/astrobiology and spectroscopy. She’ll continue to work with the biosignatures group led by Sara Seager, EAPS' Class of 1941 Professor of Planetary Sciences with appointments in the departments of Physics and Aeronautics and Astronautics. She will also work with other MIT atmospheric chemists, and the access to exoplanet data and specialists will provide Sousa-Silva with unparalleled resources. Additionally, collaborations with other groups will help ensure her spectra are of the highest quality and available to scientists: HITRAN at Harvard University, ExoMol at University College London, the Burgasser group at the University of California at San Diego, and McKemmish’s team at the University of New South Wales.</p> <p>“The literal astronomical scale of the problems that need to be solved to understand exoplanets is daunting, but very much where I feel at home,” says Sousa-Silva. “As a 51 Pegasi b fellow, I want to bridge the gap between spectroscopy and astronomy, and by doing so create a computational chemistry toolkit to identify life on an exoplanet.”</p> <p><strong>Dimming stars</strong></p> <p>Benjamin Rackham is motivated by a similar question —&nbsp;“Are we alone?” — and uses light to study exoplanets and their stars, but in a different way. As a postdoc at the University of Arizona’s Steward Observatory, Rackham examines transmission spectra from transiting exoplanets.</p> <p>“It’s phenomenal to watch the brightness of a star dim and increase again, telling you that a planet is passing in front of the star. It’s exciting to witness a secret in the sky that’s been going on for billions of years but has taken the invention of telescopes to discover,” Rackham says.</p> <p>Light that arrives at Earth from extrasolar systems contains a lot of information, both from the stars and their associated transiting exoplanets. Encoded, is data on the planet’s size, the composition of its atmosphere, the type of light emitted from the host star, distance to its star, among other things. But it’s not so straight forward; some signals can mimic or mask others, making them difficult to discern.</p> <p>One example is the transit light source effect, which happens when a star’s photosphere is not uniform and shows blemishes like starspots due to magnetic activity. This causes the emitted light to vary before, during and after a transit, making it difficult for researchers to understand what the full spectrum of the star is, and if light variations during a transit are caused by a feature of the planet’s atmosphere or originating from the star itself.</p> <p>Rackham works to disentangle these signals. As an experimentalist, he aims to pilot and refine techniques that lead to more robust observations on the true nature of such exoplanets. Systematically investigating this phenomenon on a diverse range of stars, Rackham’s research has revealed that spots on small, cool stars (red dwarfs), which tend to be more active than Sun-like stars, can produce spectral features that give the appearance of water vapor and other atmospheric traits on transiting planets.</p> <p>“This is&nbsp;problematic&nbsp;for astrobiology because these are the&nbsp;same types of stars&nbsp;that we would like to focus on to study small,&nbsp;temperate, rocky worlds that might host life,” Rackham says.</p> <p>In his fellowship at MIT working with EAPS Assistant Professor Julien de Wit, Rackham will address this problem of stars imprinting spectral features on transit depths by refining scientists’ understanding of the properties of active stars that host exoplanets. To do this, he will conduct a series of observational studies of exoplanet host stars and ultimately produce an open-source tool that untangles stellar and planetary signals, taking into account transit observations alongside high-resolution stellar spectra and long-term brightness monitoring data. Using datasets from space missions like Kepler and TESS, he will measure the properties of starspots and how they affect transmission spectra.</p> <p>This tool will be essential to studying the smallest transiting exoplanets with the James Webb Space Telescope and, in the long run, searching for atmospheric biosignatures with transits. In order to decompose these spectra, Rackham will collect highly-detailed observations and evolution of the brightness of host stars over time using the SPECULOOS telescope network, and the Magellan Telescopes located at the Las Campanas Observatory in Chile. In addition, his efforts to characterize the star TRAPPIST-1 in detail will support the study of its seven Earth-sized planets. Altogether, these contributions will be critical to catalog exoplanet atmospheres in the search of life elsewhere in the universe.</p> <p>“With the TESS mission, it’s a particularly great time for exoplanets at MIT,” says Rackham. “I’m really excited to be in the thick of the action now and, in the future, to be part of the team that seeks to find life elsewhere in the universe!”</p> <p>Other postdocs and their hosting institutions who have also received fellowships are Juliette Becker, who is joining Caltech; Cheng Li, who is joining the University of California at Berkeley; Jessica Spake, who is joining Caltech; and Xinting Yu, who is joining the University of California at Santa Cruz.</p> <p>The Heising-Simons Foundation is a family foundation based in Los Altos and San Francisco, California. The foundation works with its many partners to advance sustainable solutions in climate and clean energy, enable groundbreaking research in science, enhance the education of our youngest learners, and support human rights for all people. The fellowship not only provides up to $375,000 of support for independent research over three years, but also access to professional networks and mentorship, as well as the time and space to establish distinction and leadership in the field.</p> Clara Sousa-Silva and Benjamin Rackham will be 51 Pegasi b Fellows at MIT within the Department of Earth, Atmospheric and Planetary Sciences.Image courtesy of the Heising-Simons FoundationSchool of Science, EAPS, Planets, Planetary science, Exoplanets, Astronomy, Awards, honors and fellowships, Space, astronomy and planetary science, Graduate, postdoctoral, Aeronautical and astronautical engineering, School of Engineering MIT celebrates 50th anniversary of historic moon landing Symposium featuring former astronauts and other Apollo mission luminaries examines the program’s legacy. Fri, 15 Mar 2019 15:28:04 -0400 Jennifer Chu | MIT News Office <p>On Sept. 12, 1962, in a speech given in Houston to pump up support for NASA’s Apollo program, President John F. Kennedy shook a stadium crowd with the now-famous quote: “We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard.”</p> <p>As he delivered these lines, engineers in MIT’s Instrumentation Laboratory were already taking up the president’s challenge. One year earlier, NASA had awarded MIT the first major contract of the Apollo program, charging the Instrumentation Lab with developing the spacecraft’s guidance, navigation, and control systems that would shepherd astronauts Michael Collins, Buzz Aldrin, and Neil Armstrong to the moon and back.</p> <p>On July 20, 1969, the hard work of thousands paid off, as Apollo 11 touched down on the lunar surface, safely delivering Armstrong and Aldrin ScD ’63 as the first people to land on the moon.</p> <p>On Wednesday, MIT’s Department of Aeronautics and Astronautics (AeroAstro) celebrated the 50th anniversary of this historic event with the daylong symposium “Apollo 50+50,” featuring former astronauts, engineers, and NASA adminstrators who examined the legacy of the Apollo program, and MIT faculty, students, industry leaders, and alumni who envisioned what human space exploration might look like in the next 50 years.</p> <p>In welcoming a large audience to Kresge Auditorium, some of whom sported NASA regalia for the occasion, Daniel Hastings, head of AeroAstro, said of today’s prospects for space exploration: “It’s the most exciting time since Armstrong and Aldrin landed on the moon.”</p> <p>The event kicked off three days of programming for <a href="">MIT Space Week</a>, which also included the Media Lab’s “<a href="">Beyond the Cradle: Envisioning a New Space Age</a>” on March 14, and the student-led “<a href="">New Space Age Conference</a>” on March 15.</p> <p><strong>“We could press on”</strong></p> <p>As a “baby boomer living through Apollo,” retired astronaut Charles Bolden, NASA’s 12th administrator, said the Apollo program illustrated “how masterful we were at overcoming adversity.” In a keynote address that opened the day’s events, Bolden reminded the audience that, at the time the ambitious program got underway in the 1960s, the country was in the violent thick of the civil rights movement.</p> <p><strong>“</strong>We were killing each other in the streets,” Bolden said. “And yet we had an agency like NASA, and a small group of people, who were able to bear through everything and land on the moon. … We could recognize there were greater things we could do as a people, and we could press on.”</p> <p>For MIT’s part, the push began with a telegram on Aug. 9, 1961, to Charles Stark Draper, director of the Instrumentation Laboratory, notifying him that NASA had selected the MIT lab “to develop the guidance navigation system of the Project Apollo spacecraft.” Draper, who was known widely as “Doc,” famously assured NASA of MIT’s work by volunteering himself as a crew member on the mission, writing to the agency that “if I am willing to hang my life on our equipment, the whole project will surely have the strongest possible motivation.”</p> <p>This of course proved unnecessary, and Draper went on to lead the development of the guidance system with “unbounded optimism,” as his former student and colleague Lawrence Young, the MIT Apollo Program Professor, recalled in his remarks.</p> <p>“We owe the lighting of our fuse to Doc Draper,” Young said.</p> <p>At the time that MIT took on the Apollo project, the Instrumentation Laboratory, later renamed Draper Laboratory, took up a significant footprint, with 2,000 people and 15 buildings on campus, dedicated largely to the lunar effort.</p> <p>“The Instrumentation Lab dwarfed the [AeroAstro] department,” said Hastings, joking, “it was more like the department was a small pimple on the Instrumentation Lab.”</p> <p><strong>Apollo remembered</strong></p> <p>In a highlight of the day’s events, NASA astronauts Walter Cunningham (Apollo 7) and Charles Duke SM ’64 (Apollo 16), and MIT Instrumentation Laboratory engineers Donald Eyles and William Widnall ’59, SM ’62 — all from the Apollo era — took the stage to reminisce about some of the technical challenges and emotional moments that defined the program.</p> <p>One of the recurring themes of their conversation was the observation that things simply got done faster back then. For instance, Duke remarked that it took just 8.5 years from when Kennedy first called for the mission, to when Armstrong’s boots hit the lunar surface.</p> <p>“I would argue the proposal for such a mission would take longer [today],” Duke said to an appreciative rumble from the audience.</p> <p>The Apollo Guidance Computer, developed at MIT, weighed 70 pounds, consumed 55 watts of power — half the wattage of a regular lightbulb — and took up less than 1 cubic foot inside the spacecraft. The system was one of the first digital flight computers, and one of the first computers to use integrated circuits. &nbsp;</p> <p>Eyles and Widnall recalled in detail the technical efforts that went into developing the computer’s hardware and software. “If you’re picturing [the computer code] on a monitor, you’d be wrong,” Eyles told the audience. “We were writing the program on IBM punch cards. That clunking mechanical sound of the key-punch machine was the soundtrack to creating the software.”</p> <p>Written out, that code famously amounted to a stack of paper as tall as lead software engineer Margaret Hamilton — who was not able to participate in Wednesday’s panel but attended the symposium dinner that evening.</p> <p>In the end, the Apollo Guidance Computer succeeded in steering 15 space flights, including nine to the moon, and six lunar landings. That’s not to say that the system didn’t experience some drama along the way, and Duke, who was the capsule communicator, or CAPCOM, for Apollo 11, remembers having to radio up to the spacecraft during the now-famous rocky landing.</p> <p>“When I heard the first alarm go off during the braking phase, I thought we were dead in the water,” Duke said of the first in a series of alerts that the Apollo astronauts reported, indicating that the computer was overloaded, during the most computationally taxing phase of the mission. The spacecraft was several miles off course and needed to fly over a “boulder field,” to land within 60 seconds or risk running out of fuel.</p> <p>Flight controllers in Houston’s Mission Control Center determined that if nothing else went wrong, the astronats, despite the alarms, could proceed with landing.</p> <p>“Tension was high,” Duke said of the moment. “You didn’t want to touch down on a boulder and blow a nozzle, and spoil your whole day.”</p> <p>When the crew finally touched down on the Sea of Tranquility, with Armstrong’s cool report that “the Eagle has landed,” Duke, too wound-up to properly verbalize the callback “Tranquility,” recalls “I was so excited … it came out as ‘Twang,’ or something like that.’ The tension — it was like popping a balloon.”</p> <p>Since the Apollo era, NASA has launched astronauts on numerous missions, many of whom are MIT graduates. On Wednesday, 13 of those graduates came onstage to be recognized along with the Apollo crew.</p> <p>In introducing them to the audience, Jeffrey Hoffman, a former astronaut and now AeroAstro professor of the practice, noted MIT’s significant representation in the astronaut community. For instance, in the five missions to repair the Hubble Space Telescope, which comprised 24 spacewalks, 13 of those were performed by MIT graduates.</p> <p>“That’s pretty cool,” Hoffman said.</p> <p><strong>On the horizon</strong></p> <p>The Apollo moon rocks that were were brought back to Earth have “evolved our understanding of how the moon formed,” said Maria Zuber, MIT’s vice president for research and the E.A. Griswold Professor of Geophysics in the Department of Earth, Atmospheric and Planetary Sciences. These rocks “vanquished” the idea that the moon originally formed as a cold assemblage of rocks and “foo foo dust,” she said.</p> <p>Instead, after carefully analyzing samples from Apollo 11 and other missions, scientists at MIT and elsewhere have found that the moon was a dynamic body, with a surface that at one time was entirely molten, and a metallic core, or “dynamo,” powering an early, lunar magnetic field. Even more provocative was the finding that the moon was not in fact “bone-dry,” but actually harbored water — an idea that Zuber said was virtually unpublishable until an MIT graduate reported evidence of water in Apollo samples, after which the floodgates opened in support of the idea.</p> <p>To consider the next 50 years of space exploration, the MIT symposium featured a panel of faculty members — Paulo Lozano, Danielle Wood, Richard Binzel, and Sara Seager — who highlighted, respectively, the development of tiny thrusters to power miniature spacecraft; an effort to enable wider access to microgravity missions; an MIT student-designed mission (REXIS) that is currently analyzing the near-Earth asteroid Bennu; and TESS and ASTERIA, satellite missions that are currently in orbit, looking for planets and possibly, life, outside our solar system.</p> <p>Industry leaders also weighed in on the growing commercialization of space exploration, in a panel, moderated by Olivier de Weck, Professor of Aeronautics and Astronautics and Engineering Systems, featuring MIT alums who currently head major aerospace companies.</p> <p>Keoki Jackson, chief technology officer of Lockheed Martin, noted the pervasiveness of space-based technologies, such as GPS-dependent apps for everything from weather and news, to Uber.</p> <p>“[Commercial enterprises] have made space a taken-for-granted part of life,” said Jackson, noting later in the panel that in 2015, 1 billion GPS devices had been sold around the world. “This shows you what can happen exponentially when you come up with something truly enabling.”</p> <p>“The challenge we face is talent, and in particular, diversity,” said John Langford, CEO and founder of Aurora Flight Sciences, who noted the panel’s all-male participants as an example. “It’s an industry-wide challenge. We’re working to reform ourselves, as we move from the brigade-type technologies that we grew up with, to incorporating technologies such as computer technology and artificial intelligence.”</p> <p><strong>Future missions</strong></p> <p>In a glimpse of what the future of space exploration might hold, MIT students presented lightning talks on a range of projects, including a custom-designed drill to excavate ice on Mars, a system that makes oxygen on Mars to fuel return missions to Earth, and a plan to send CubeSats around the world to monitor water vapor as a measure of climate change.</p> <p>Audience members voted online for the best pitch, which ultimately went to <a href="">Raichelle Aniceto</a> and her presentation of a CubeSat-enabled laser communications system designed to transmit large amounts of data from the moon to Earth in just five minutes.</p> <p>In the last keynote address of the symposium, Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, told the audience that there is still a lot of research to be done on the moon, which he said is changing, as evidenced by new craters that have formed in the last 50 years.</p> <p>“The moon of the Apollo era is not the same moon of today,” said Zurbuchen, who noted that just this week, NASA announced it will open previously unlocked samples of soil collected by the Apollo missions.</p> <p>In closing the symposium, Dava Newman, the Apollo Program Professor of Astronautics and former NASA deputy administrator, envisioned a future dedicated to sending humans back to the moon, and ultimately to Mars.</p> <p>“I’m a rocket scientist. I got here because of Apollo, and Eleanor Roosevelt said it best: Believe in the beauty of your dreams,” Newman said. “The challenge is, within 50 years, to be boots on Mars. I think we have the brains and the doers and inspiration to really make that happen.”</p> The Apollo astronauts and engineers were joined onstage by some of MIT’s astronaut alumni, including two active astronauts, Mike Fincke and Warren Hoburg (in blue jackets).Photo: Jake BelcherAeronautical and astronautical engineering, Astronomy, Astrophysics, EAPS, Mars, NASA, Planetary science, Research, Satellites, School of Engineering, space, astronomy and planetary science, Special events and guest speakers, MIT History, History of science Microgravity research after the International Space Station Researchers say new facilities in space should be available to scientists from any country. Tue, 12 Mar 2019 23:00:06 -0400 Jennifer Chu | MIT News Office <p><em>For nearly 20 years, the International Space Station (ISS) has served as a singular laboratory for thousands of scientists, students, and startups around the world, who&nbsp; have accessed the station’s microgravity environment to test how being in space impacts everything from cancer cells and human tissues to zucchini and barley seeds — not to mention a host of living organisms including flatworms, ants, geckos, and bobtail squids. </em></p> <p><em>Indeed, the ISS “has operated as a bastion of international cooperation and a unique testbed for microgravity research,” write MIT engineers in a paper they presented on March 8 at the IEEE Aerospace Conference in Montana. But the ISS will eventually be retired in its current form. NASA is preparing to transition the focus of its human space flight activities to the Moon, and the international partners that manage the ISS are discussing how to transition out of the current operational model. </em></p> <p><em>As NASA explores options for commercial entities to operate research platforms in orbit around Earth, and while other public and private entities consider alternative designs for microgravity facilities, the MIT team says it’s important to keep affordable access to such facilities at the forefront of these discussions. In their paper, the researchers argue that scientists from any country should be able to participate in microgravity research. </em></p> <p><em>Toward that end, the team has developed a tool for evaluating the accessibility of various “governance models,” such as facilities that are controlled by mostly governments or private entities, or a mixture of both. </em></p> <p><em>MIT News checked in with the researchers about the future of microgravity research and how openness can drive innovation and collaboration in space. Christine Joseph is a graduate student in MIT’s Department of Aeronautics and Astronautics and the Technology and Policy Program. Danielle Wood is the Benesse Corporation Career Development Assistant Professor of Research in Education</em><em> within MIT’s Program in Media Arts and Sciences and jointly appointed in the Department of Aeronautics and Astronautics. She is also founder of the Space Enabled Research Group within the MIT Media Lab, whose mission is to advance justice in Earth’s complex systems using designs enabled by space.</em></p> <p><strong>Q:</strong> Why is affordable access important, particularly for space-based microgravity research?</p> <p><strong>Wood:</strong> Participation in space-based microgravity research should be an opportunity open to researchers from every nation because space is a global commons that does not belong to a single nation. As stated in the Outer Space Treaty, ratified by over 100 countries, “the exploration and use of outer space … shall be carried out for the benefit and in the interests of all countries … and shall be the province of all [hu]mankind.”</p> <p>Studies in the microgravity environment bring new knowledge about the human body, plants, animals, materials, physics, manufacturing, and medicines. This knowledge can contribute to sustainable development when it is translated into Earth-based applications, such as when knowledge of astronaut exercise routines informs recovery procedures for patients facing long periods of bedrest, or when experiments about the physics of combustion yield results that can improve fire safety <a href="">on Earth</a>.</p> <p>When a larger variety of researchers from around the world participate in microgravity research, the scientific community benefits from the broader range of research outcomes. Participation in microgravity research also helps countries that do not yet have experience in space build local capability to design and operate space-based experiments.</p> <p><strong>Q:</strong> How does your new tool evaluate accessibility to microgravity research facilities?</p> <p><strong>Joseph:</strong> We propose that accessibility can be measured using the metrics of economic and administrative openness. Economic openness is based on the financial costs paid by researchers to perform all the activities involved with completing a microgravity research project. This includes the costs associated with designing an experiment, engineering it to be safe and functional, launching it to space, accessing a facility that provides environmental control, data and power, operating the experiment, and possibly returning it to Earth.</p> <p>Administrative openness refers to the type of gatekeeping that directly and indirectly determines who can participate. For example, today administrative procedures influence access depending on the nationality or type of organization the user comes from and the type of microgravity activity they are seeking. We map future microgravity research facilities and their governance policies along these dimensions of economic and administrative openness. Using these two metrics, we can rate the overall accessibility of a future marketplace for microgravity research.</p> <p><strong>Wood:</strong> Our goal is to encourage a dialogue about the value of providing access to this unique research environment. Many stakeholders — governments, companies, international organizations — may influence the rules that determine who sends micrgravity research to space after the International Space Station is retired. Thus far, the world has not experienced a microgravity research marketplace that is fully driven by commercial forces with prices set by a free market, because governments have subsidized the cost of research access as a public service. This work highlights the need to evaluate future policy and commercial proposals based on the needs of those that have the least access and experience with microgravity research today.</p> <p><strong>Q:</strong> What type of facility or structure have you found, through your tool, can provide the most affordable access to microgravity research, and what will it take to launch such a model?</p> <p><strong>Joseph:</strong> Although not ideal, our current structure has evolved to become surprisingly accessible. Faciliators like the United Nations Office for Outer Space Affairs help to broker access for emerging space nations by working with some of the “gatekeeper” space agencies that built the ISS. Commercial companies have also started to build and operate their own modules attached to the ISS that almost any user can buy access to. The ISS has become this interesting conglomeration of public, private, commercial, and international entities. So far, none of the other proposals for space stations in low Earth orbit (up to about 2,000 kilometers from the Earth’s surface) are mature enough to determine whether they will have a similar level of accessibility as the current environment.</p> <p>However, we can always do better. Building the ISS was the single largest and most expensive construction project in human history and it involved effort from many countries. There are a lot of lessons to be learned from the development of the ISS in terms of technical and policy models. We also need to take into account the expectations of the commercial companies that will participate in the emerging commercial space economy in low Earth orbit.</p> <p>The “spaces in space” that we operate in are evolving dramatically. It is not too early to examine how policies and investment decisions will shape the nature of accessibility for microgravity research beyond the International Space Station. Thinking about accessibility now is important to help ensure that microgravity research remains the province of all humankind.</p> Danielle Wood (left) and Christine Joseph.Image: Zero Gravity Corporation3 Questions, Aeronautical and astronautical engineering, Media Lab, NASA, Policy, Research, Satellites, School of Architecture and Planning, space, astronomy and planetary science, Technology and society