George Sinker

George Sinker (5 May 1900 – 19 January 1986) was bishop of Nagpur and provost of Birmingham Cathedral.
He was born in Hyderabad, India, the son of the Reverend R Sinker, and was educated at Rossall School and Brasenose College, Oxford. In 1924 he married Eva Margaret, daughter of Colonel C H Madden OBE MC.
He served as a missionary for the Church Missionary Society in Kandy and Ceylon starting in 1921. In 1924 he was ordained in Bannu, North West Frontier Province, India. He moved to Peshawar in 1932. He was appointed headmaster of the Bishop Cotton School, Simla, in 1935, then canon of the Cathedral Church of the Resurrection, Lahore, 1944, and general secretary of the Bible Society for India and Ceylon in 1947. He was consecrated bishop of Nagpur in 1949.
On his return to the United Kingdom, he was successively Vicar of Bakewell (and an Assistant Bishop of Derby) from 1954 to 1962 and Provost of Birmingham Cathedral (and an Assistant Bishop of Birmingham) from 1962 to 1972. He died in Macclesfield in 1986.


Tucana in Chinese astronomy

The modern constellation Tucana is not included in the Three Enclosures and Twenty-Eight Mansions system of traditional Chinese uranography because its stars are too far south for observers in China to know about them prior to the introduction of Western star charts. Based on the work of Xu Guangqi and the German Jesuit missionary Johann Adam Schall von Bell in the late Ming Dynasty, this constellation has been classified as one of the 23 Southern Asterisms (近南極星區, "Jìnnánjíxīngōu") under the name Crane (鶴, "Hè") and Bird's Beak (鳥喙, "Niǎohuì").
The name of the western constellation in modern Chinese is 杜鵑座 ("dù juān zuò"), meaning "the cuckoo constellation".
Stars.
The map of Chinese constellation in constellation Tucana area consists of :


Clare Parnell

Clare Elizabeth Parnell (born 1970) is a British astrophysicist and applied mathematician who studies the mathematics of the sun and of magnetic fields, including the Solar corona and the sun's magnetic carpet, magnetic reconnection in plasma, and the null points of magnetic fields. She is a professor of mathematics at the University of St Andrews, and the former head of the Division of Applied Mathematics at St Andrews.
Education and career.
Parnell was born in Essex and educated at The Ridgeway School and Swindon Technical College. As a child, she found mathematics to be her easiest subject. She entered the University of Wales College Cardiff in 1988, originally intending to study both chemistry and mathematics, but after a year switched to mathematics only.
In 1991 she completed a bachelor's degree with first class honours in mathematics at Cardiff. She then came to the University of St Andrews as a doctoral student, finishing her Ph.D. in theoretical solar physics in 1994.
She remained at St Andrews as a postdoctoral researcher (interrupted by research at Stanford University in 1996–1997), became a lecturer in 2002, and was promoted to professor in 2011. From 2009 to 2013 she was head of the Division of Applied Mathematics at St Andrews.
Recognition.
In 2006, Parnell won the Fowler Prize for Early Achievement in Astronomy and Geophysics of the Royal Astronomical Society for her research on how the Solar corona is heated. In 2007 she won a Philip Leverhulme Prize for her work on solar physics.
Personal.
Parnell is an avid mountaineer and chose the University of Wales in part for its nearby mountains. In her three years as a doctoral student at St Andrews, she climbed all 277 peaks then listed as Munros. She has two children.


May 2003 lunar eclipse

A total lunar eclipse took place on May 16, 2003, the first of two total lunar eclipses in 2003, the other being on November 9, 2003.
This lunar eclipse is first of a "tetrad", four total lunar eclipses in series. The previous series was in 1985 and 1986, starting with a May 1985 lunar eclipse. The next one was in , starting with the April 15, 2014 lunar eclipse.
Relation to other lunar eclipses.
Lunar year series.
It is also the second of four lunar year cycles, repeating every 354 days.
Metonic series.
This eclipse is the second of four Metonic cycle lunar eclipses on the same date, May 15–16, each separated by 19 years.
Half-Saros cycle.
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros). This lunar eclipse is related to two annular solar eclipses of Solar Saros 128.


George Winder

George Alexander Winder (16 July 1850 – 1 February 1913) was an English cricketer active from 1869 to 1871 who played for Lancashire. He was born in Bolton and died in Ottery St Mary. He appeared in four first-class matches as a righthanded batsman, scoring 64 runs with a highest score of 22 and held one catch. His cricket career was ended by a shooting accident in January 1872 in which he lost his left hand when his gun exploded.
Winder was educated at Rossall School and Christ's College, Cambridge. After graduating from Cambridge he attended the Royal Agricultural College, Cirencester. He was land agent to Sir Ivor Guest and then to Sir John Kennaway.


Jacqueline van Gorkom

Jacqueline Henriëtte van Gorkom (born 30 March 1947) is a Dutch radio astronomer and Rutherfurd Professor of Astronomy at Columbia University. Van Gorkom is known for her contributions to the field of galaxy evolution, particularly through observations of neutral hydrogen gas.
Education and career.
Jacqueline van Gorkom was born in Voorburg. She received her Ph.D. in astronomy from the University of Groningen Kapteyn Astronomical Institute in 1980. She worked at the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico for 8 years as a research scientist before joining the faculty at Columbia in 1988. She has held visiting appointments at the Raman Research Institute, Princeton University, California Institute of Technology, University of California, Berkeley, and the Kapteyn Institute. She has served as Chair and Director of Graduate Studies for the Department of Astronomy and is currently the Rutherfurd Professor of Astronomy at Columbia.
Research.
Van Gorkom specializes in studies of neutral hydrogen, the most abundant element in the Universe, through observations of the 21cm hydrogen line. Her research focuses on the structure and evolution of galaxies and the role of gas in galaxy formation. Her research aims to address questions such as:
She currently leads the COSMOS HI Large Extra-galactic Survey (CHILES) project, a 1000-hour observation using the Very Large Array. CHILES will study the morphology and kinematics of gas in galaxies between redshift z=0 and z=0.45 and serve as a pathfinder experiment for the Square Kilometre Array.


Yardymly (meteorite)

The Yardymly meteorite (also known as Aroos meteorite, or "Ərus meteoriti") is an iron meteorite that fell in Yardymli Rayon, Azerbaijan on November 24, 1959. The remains were discovered in the nearby village of Aroos. With five individual specimens, the total weight of the meteorite is estimated at . The meteorite is kept in the Institute of Geology of Azerbaijan National Academy of Sciences. According to the director of Şamaxı Astrophysical Observatory Eyub Guliyev, the Yardymli meteorite may originate from the shower of Perseids.
The eyewitnesses saw the bright bolide flying through clouds from southwest to northeast. The falling was accompanied by a bright, blinding flare brighter than solar illumination and a noise similar to rolling thunder. The illumination embraced the area of ca. . The fall of individual pieces was accompanied by a whistling and drone, resembling that produced by a jet aircraft or missile. The examination of chemical and physical properties of the meteorite was led by Azeri researcher Mirali Qashqai. The meteorite features a sizeable Widmanstätten pattern and an anomalously low amount of tritium. Similar tritium anomalies were detected previously in other iron meteorites.
At the request of American scientists, the Soviet Meteorite Committee sent the meteorite samples to California University, Cambridge Astrophysical Observatory and the Institute for Nuclear Researches of Chicago University, as well as to CERN. One of the samples was preserved in Fersman Mineralogical Museum.
Individual pieces.
In order of discovery:


Coronal hole

Coronal holes are areas where the Sun's corona is colder, hence darker, and has lower-density plasma than average because there is lower energy and gas levels. Coronal holes are part of the Sun's corona and are constantly changing and reshaping because the corona is not uniform. The Sun contains magnetic fields that arch away from areas in the corona that are very thin due to the lower levels of energy and gas, which cause coronal holes to appear when they do not fall back. Thus, solar particles escape at a rate great enough to create a lower density and lower temperature in that area.
First discoveries.
In the 1960s, they showed up on X-ray images taken by sounding rockets and in observations at radio wavelengths by the Sydney Chris Cross radio telescope, but at the time it was unclear what they were. Their true nature was recognized in the 1970s when X-ray telescopes in the Skylab mission were flown above the Earth's atmosphere to reveal the structure of the corona.
Solar cycle.
Coronal hole size and population correspond with the solar cycle. As the Sun heads toward solar maximum the coronal holes move closer and closer to the Sun's poles. During solar maximum, the number of coronal holes decreases until the magnetic fields on the Sun reverse. Afterwards new coronal holes appear near the new poles. The coronal holes then increase in size and number, extending farther from the poles as the Sun moves toward solar minimum again. There are permanent coronal holes on the north and south poles of the Sun.
Coronal holes and solar wind.
Coronal holes generally discharge solar wind at a speed about twice the average. The escaping solar wind is known to travel along open magnetic field lines that pass through the coronal hole area. Since coronal holes are regions in the Sun's corona that have much lower densities and temperatures than most of the corona, these regions are very thin. This thinness contributes to the solar wind since particles within the chromosphere can more easily break through.
Influence on space weather.
During solar minima coronal holes are the primary sources of space weather disturbances. Typically, geomagnetic (and proton) storms originating from coronal holes have a gradual commencement (over hours) and are not as severe as storms caused by coronal mass ejections (CMEs), which usually have a sudden onset. Due to the fact coronal holes can last for several months, it is often possible to predict the recurrence of this type of disturbance significantly farther in advance than for CME related disturbances.


Guyu

The traditional Chinese lunisolar calendar divide a year into 24 solar terms. Gǔyǔ, "Kokuu", "Gogu", or "Cốc vũ" is the 6th solar term. It begins when the Sun reaches the celestial longitude of 30° and ends when it reaches the longitude of 45°. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 30°. In the Gregorian calendar, it usually begins around April 20 and ends around May 5.
Pentads.
Each solar term can be divided into 3 pentads (候). They are: first pentad (初候), second pentad (次候) and last pentad (末候). Pentads in Guyu include:


Superflare

Superflares are very strong explosions observed on stars with energies up to ten thousand times that of typical solar flares. The stars in this class satisfy conditions which should make them solar analogues, and would be expected to be stable over very long time scales.
The original nine candidates were detected by a variety of methods. No systematic study was possible until the launch of the Kepler satellite, which monitored a very large number of solar-type stars with very high accuracy for an extended period. This showed that a small proportion of stars had violent outbursts, up to 10,000 times as powerful as the strongest flares known on the Sun. In many cases there were multiple events on the same star. Younger stars were more likely to flare than old ones, but strong events were seen on stars as old as the Sun.
The flares were initially explained by postulating giant planets in very close orbits, such that the magnetic fields of the star and planet were linked. The orbit of the planet would warp the field lines until the instability released magnetic field energy as a flare. However, no such planet has showed up as a Kepler transit and this theory has been abandoned.
All superflare stars show quasi-periodic brightness variations interpreted as very large starspots carried round by rotation. Spectroscopic studies found spectral lines that were clear indicators of chromospheric activity associated with strong and extensive magnetic fields. This suggests that superflares only differ in scale from solar flares.
Attempts have been made to detect past solar superflares from nitrate concentrations in polar ice, from historical observations of auroras, and from those radioactive isotopes that can be produced by solar energetic particles. Although three events and a few candidates have been found in the carbon-14 records in tree rings, it is not possible to associate them definitely with superflare events.
Solar superflares would have drastic effects, especially if they occurred as multiple events. Since they can occur on stars of the same age, mass and composition as the Sun this cannot be ruled out, but no indication of solar superflares have been found for the past ten millennia. However, solar-type superflare stars are very rare and are magnetically much more active than the Sun; if solar superflares do occur, it may be in well-defined episodes that occupy a small fraction of its time.
Superflare stars.
A superflare star is not the same as a flare star, which usually refers to a very late spectral type red dwarf. The term is restricted to large transient events on stars that satisfy the following conditions:
Essentially such stars may be regarded as solar analogues.
Originally nine superflare stars were found, some of them similar to the Sun.
Original superflare candidates.
The original paper identified nine candidate objects from a literature search:
Type gives the spectral classification including spectral type and luminosity class.
V (mag) means the normal apparent visual magnitude of the star.
EW(He) is the equivalent width of the 5875.6Å He I D3 line seen in emission.
The observations vary for each object. Some are X-ray measurements, others are visual, photographic, spectroscopic or photometric. The energies for the events vary from 2 × 1033 to 2 × 1038 ergs.
Kepler discoveries.
The Kepler spacecraft is a space observatory designed to find planets by the method of transits. A photometer continually monitors the brightness of 150,000 stars in a fixed area of the sky (in the constellations of Cygnus, Lyra and Draco) to detect changes in brightness caused by planets passing in front of the stellar disc. More than 90,000 are G-type stars (similar to the Sun) on or near the main sequence. The observed area corresponds to about 0.25% of the entire sky. The photometer is sensitive to wavelengths of 400–865 nm: the entire visible spectrum and part of the infrared. The photometric accuracy achieved by Kepler is typically 0.01% (0.1 mmag) for 30 minute integration times of 12th magnitude stars.
G-type stars.
The high accuracy, the large number of stars observed and the long period of observation make Kepler ideal for detecting superflares. Studies published in 2012 and 2013 involved 83,000 stars over a period of 500 days (much of the data analysis was carried out with the help of five first-year undergraduates). The stars were selected from the Kepler Input Catalog to have Teff, the effective temperature, between 5100 and 6000K (the solar value is 5750K) to find stars of similar spectral class to the Sun, and the surface gravity log g > 4.0 to eliminate sub-giants and giants. The spectral classes range from F8 to G8. The integration time was 30 min in the original study. 1547 superflares were found on 279 solar-type stars.The most intense events increased the brightness of the stars by 30% and had an energy of 1036 ergs. White-light flares on the Sun change the brightness by about 0.01%, and the strongest flares have a visible-light energy of about 1032 ergs. (All energies quoted are in the optical bandpass and so are lower limits since some energy is emitted at other wavelengths.) Most events were much less energetic than this: flare amplitudes below 0.1% of the stellar value and energies of 2 × 1033 ergs were detectable with the 30 minute integration. The flares had a rapid rise followed by an exponential decay on a time scale of 1–3 hours. The most powerful events corresponded to energies ten thousand greater than the largest flares observed on the Sun. Some stars flared very frequently: one star showed 57 events in 500 days, a rate of one every nine days. For the statistics of flares, the number of flares decreased with energy E roughly as E−2, a similar behaviour to solar flares. The duration of the flare increased with its energy, again in accordance with the solar behaviour.
Some Kepler data is taken at one minute sampling, though inevitably with lower accuracy. Using this data, on a smaller sample of stars, reveals flares that are too brief for reliable detection with 30-min integrations, allowing detection of events as low as 1032 ergs, comparable with the brightest flares on the Sun. The occurrence frequency as a function of energy remains a power law E−n when extended to lower energies, with n around 1.5. At this time resolution some superflares show multiple peaks with separations of 100 to 1000 seconds, again comparable to the pulsations in solar flares. The star KIC 9655129 showed two periods, of 78 and 32 minutes, suggesting magnetohydrodynamic oscillations in the flaring region. These observations suggest that superflares are different only in scale and not in type to solar flares.
Superflare stars show a quasi-periodic brightness variation, which is interpreted as evidence of starspots carried around by solar rotation. This allows an estimate of the rotation period of the star; values range from less than one day up to tens of days (the value for the Sun is 25 days). On the Sun, radiometer monitoring from satellites shows that large sunspots can reduce the brightness by up to 0.2%. In superflare stars the most common brightness variations are 1-2%, though they can be as great as 7-8%, suggesting that the area of the starspots can be very much larger than anything found on the Sun. In some cases the brightness variations can be modelled by only one or two large starspots, though not all cases are so simple. The starspots could be groups of smaller spots or single giant spots.
Flares are more common in stars with short periods. However, the energy of the largest flares is not related to the period of rotation. Stars with larger variations also have much more frequent flares; there is as well a tendency for them to have more energetic flares. Large variations can be found on even the most slowly rotating stars: one star had a rotation period of 22.7 days and variations implying spot coverage of 2.5% of the surface, over ten times greater than the maximum solar value. By estimating the size of the starspots from the amplitude variation, and assuming solar values for the magnetic fields in the spots (1000 G), it is possible to estimate the energy available: in all cases there is enough energy in the field to power even the largest flares observed. This suggests that superflares and solar flares have essentially the same mechanism.
In order to determine whether superflares can occur on the Sun, it is important to narrow the definition of Sun-like stars. When the temperature range is divided into stars with Teff above and below 5600K (early and late G-type stars), stars of lower temperature are about twice as likely to show superflare activity as those in the solar range and those that do so have more flares: the occurrence frequency of flares (number per star per year) is about five times as great in the late-type stars. It is well known that both the rotation rate and the magnetic activity of a star decrease with age in G-type stars. When flare stars are divided into fast and slow rotators, using the rotation period estimated from brightness variations, there is a general tendency for the fastest-rotating (and presumably youngest) stars to show a greater probability of activity: in particular, stars rotating in less than 10 days are 20-30 times more likely to have activity. Nevertheless, 44 superflares were found on 19 stars with similar temperatures to the Sun and periods greater than 10 days (out of 14000 such stars examined); four superflares with energies in the range 1-5 × 1033 ergs were detected on stars rotating more slowly than the Sun (of about 5000 in the sample). The distribution of flares with energy has the same shape for all classes of star: although Sun-like stars are less likely to flare, they have the same proportion of very energetic flares as younger and cooler stars.
K and M type stars.
Kepler data have also been used to search for flares on stars of later spectral types than G. A sample of 23,253 stars with effective temperature Teff less than 5150K and surface gravity log g > 4.2, corresponding to main sequence stars later than K0V, was examined for flares over a time period of 33.5 days. 373 stars were identified as having obvious flares. Some stars had only one flare, while others showed as many as fifteen. The strongest events increased the brightness of the star by 7-8%. This is not radically different from the peak brightness of flares on G-type stars; however, since K and M stars are less luminous than type G, this suggests that flares on these stars are less energetic. Comparing the two classes of stars studied, it seems that M stars flare more frequently than K stars but the duration of each flare tends to be shorter. It is not possible to draw any conclusions about the relative proportion of G and K type stars showing superflares, or about the frequency of flares on those stars that do show such activity, since the flare detection algorithms and criteria in the two studies are quite different.
Most (though not all) of the K and M stars show the same quasi-periodic brightness variations as the G stars. There is a tendency for more energetic flares to occur on more variable stars; however flare frequency is only weakly related to variability.
Hot Jupiters as an explanation.
When superflares were originally discovered on solar-type stars it was suggested that these eruptions may be produced by the interaction of the star's magnetic field with the magnetic field of a gas-giant planet orbiting so close to the primary that the magnetic fields were linked. Rotation or orbital motion would wind up the magnetic fields until a reconfiguration of the fields would cause an explosive release of energy. The RS Canum Venaticorum variables are close binaries, with orbital periods between 1 and 14 days, in which the primary is an F- or G-type main sequence star, and with strong chromospheric activity at all orbital phases. These systems have brightness variations attributed to large starspots on the primary; some show large flares thought to be caused by magnetic reconnection. The companion is close enough to spin up the star by tidal interactions.
A gas giant however would not be massive enough to do this, leaving the various measurable properties of the star (rotation speed, chromospheric activity) unchanged. If the giant and the primary were close enough for the magnetic fields to be linked, the orbit of the planet would wrap the field lines until the configuration became unstable followed by a violent release of energy in the form of a flare. Kepler discovered a number of closely orbiting gas giants, known as hot Jupiters; studies of two such systems showed periodic variations of the chromospheric activity of the primary synchronised to the period of the companion.
Not all planetary transits can be detected by Kepler, since the planetary orbit may be out of the line of sight to Earth. However, the hot Jupiters orbit so close to the primary that the chance of a transit is about 10%. If superflares were caused by close planets the 279 flare stars discovered should have about 28 transiting companions; none of them actually showed evidence of transits, effectively excluding this explanation.
Spectroscopic observations of superflare stars.
Spectroscopic studies of superflares allow their properties to be determined in more detail, in the hope of detecting the cause of the flares. The first studies were made using the high dispersion spectrograph on the Subaru telescope in Hawaii. Some 50 apparently solar-type stars, known from the Kepler observations to show superflare activity, have been examined in detail. Of these, only 16 showed evidence of being visual or spectroscopic binaries; these were excluded since close binaries are frequently active, while in the case of visual binaries there is the chance of activity taking place on the companion. Spectroscopy allows accurate determinations of the effective temperature, the surface gravity and the abundance of elements beyond helium ('metallicity'); most of the 34 single stars proved to be main sequence stars of spectral type G and similar composition to the Sun. Since properties such as temperature and surface gravity change over the lifetime of a star, stellar evolution theory allows an estimate of the age of a star: in most cases the age appeared to be above several hundred million years. This is important since very young stars are known to be much more active. Nine of the stars conformed to the narrower definition of solar-type given above, with temperatures greater than 5600K and rotation periods longer than 10 days; some had periods above 20 or even 30 days. Only five of the 34 could be described as fast rotators.
Observations from LAMOST have been used to measure chromospheric activity of 5,648 solar-like stars in the Kepler field, including 48 superflare stars. These observations show that superflare stars are generally characterized by larger chromospheric emissions than other stars, including the Sun. However, superflare stars with activity levels lower than, or comparable to, the Sun do exist, suggesting that solar flares and superflares most likely share the same origin. The very large ensemble of solar-like stars included in this study enables detailed and robust estimates of the relation between chromospheric activity and the occurrence of superflares.
All the stars showed the quasi-periodic brightness variations, ranging from 0.1% to nearly 10%, interpreted as the rotation of large starspots. When large spots exist on a star, the activity level of the chromosphere becomes high; in particular, large chromospheric plages form around sunspot groups. The intensities of certain solar and stellar lines generated in the chromosphere, particularly the lines of ionised calcium (Ca II) and the Hα line of hydrogen, are known to be indicators of magnetic activity. Observations of the Ca lines in stars of similar age to the Sun even show cyclic variations reminiscent of the 11 year solar cycle. By observing certain infrared lines of Ca II for the 34 superflare stars it was possible to estimate their chromospheric activity. Measurements of the same lines at points within an active region on the Sun, together with simultaneous measurements of the local magnetic field, show that there is a general relation between field and activity.
Although the stars show a clear correlation between rotational speed and activity, this does not exclude activity on slowly rotating stars: even stars as slow as the Sun can have high activity. All the superflare stars observed had more activity than the Sun, implying larger magnetic fields. There is also a correlation between the activity of a star and its brightness variations (and therefore the starspot coverage): all stars with large amplitude variations showed high activity.
Knowing the approximate area covered by starspots from the size of the variations, and the field strength estimated from the chromospheric activity, allows an estimate of the total energy stored in the magnetic field; in all cases there was enough energy stored in the field to account for even the largest superflares. Both the photometric and the spectroscopic observations are consistent with the theory that superflares are different only in scale from solar flares, and can be accounted for by the release of magnetic energy in active regions very much larger than those on the Sun. Nevertheless, these regions can appear on stars with masses, temperatures, compositions, rotation speeds and ages similar to the Sun.
See also Chromosphere#On other stars
Detecting past superflares on the Sun.
Since stars apparently similar to the Sun can produce superflares it is natural to ask if the Sun itself can do so, and to try to find evidence that it has done in the past. Large flares are invariably accompanied by energetic particles, and these particles produce effects if they reach the earth. The Carrington event of 1859, the largest flare of which we have direct observation, produced global auroral displays extending close to the equator. Energetic particles can produce chemical changes in the atmosphere, which can be permanently recorded in the polar ice. Fast protons generate distinctive isotopes, particularly carbon-14, which can be taken up and preserved by living creatures.
Nitrate concentrations in polar ice.
When solar energetic particles reach the Earth's atmosphere they cause ionisation that creates nitric oxide (NO) and other reactive nitrogen species, which then precipitate out in the form of nitrates. Since all energetic charged particles are deflected to a greater or lesser extent by the geomagnetic field, they enter preferentially at the polar latitudes; since high latitudes also contain permanent ice, it is natural to look for the nitrate signature of particle events in ice cores. A study of a Greenland ice core extending back to 1561 AD achieved resolutions of 10 or 20 samples a year, allowing in principle the detection of single events. Precise dates (within one or two years) can be achieved by counting annual layers in the cores, checked by identification of deposits associated with known volcanic eruptions. The core contained an annual variation of nitrate concentration, accompanied by a number of 'spikes' of different amplitudes. The strongest of these in the entire record was dated to within a few weeks of the Carrington event of 1859. However, other events can produce nitrate spikes, including biomass burning which also produces enhanced ammonium concentrations. An examination of fourteen ice cores from Antarctic and Arctic regions showed large nitrate spikes: however, none of them were dated to 1859 other than the one already mentioned, and that one seems to be too soon after the Carrington event and too short to be explained by it. All such spikes were associated with ammonium and other chemical indicators of combustion. The conclusion is that nitrate concentrations cannot be used as indicators of historic solar activity.
Single events from cosmogenic isotopes.
When energetic protons enter the atmosphere they create isotopes by reactions with the major components; the most important of these is carbon-14 (14C), which is created when secondary neutrons react with nitrogen. 14C, which has a half-life of 5,730 years, reacts with oxygen to form carbon dioxide which is taken up by plants; dating wood by its 14C content was the original basis of radiocarbon dating. If wood of known age is available the process can be reversed. Measuring the 14C content and using the half-life allows estimation of the content when the wood was formed. The growth rings of trees show patterns, caused by various environmental factors: dendrochronology uses these growth rings of trees, compared across overlapping sequences, to establish accurate dates. Applying this method shows that atmospheric 14C does indeed vary with time, due to solar activity. This is the basis of the carbon dating calibration curve. Clearly, it can also be used to detect any peaks in production caused by solar flares, if those flares create enough energetic particles to produce a measurable increase in 14C.
An examination of the calibration curve, which has a time resolution of five years, showed three intervals in the last 3,000 years in which 14C increased significantly. On the basis of this two Japanese cedar trees were examined with a resolution of a single year, and showed an increase of 1.2% in AD 774, some twenty times larger than anything expected from the normal solar variation. This peak steadily diminished over the next few years. The result was confirmed by studies of German oak, bristlecone pine from California, Siberian larch, and Kauri wood from New Zealand. All determinations agreed on both the time and amplitude of the effect. In addition, measurements of coral skeletons from the South China Sea showed substantial variations in 14C over a few months around the same time; however, the date could only be established to within a period of ±14 years around 783 AD.
Carbon-14 is not the only isotope that can be produced by energetic particles. Beryllium-10 (10Be, half-life 1.4 million years) is also formed from nitrogen and oxygen, and deposited in polar ice. However, 10Be deposition can be strongly related to local weather and shows extreme geographic variability; it is also more difficult to assign dates. Nevertheless, a 10Be increase during the 770s was found in an ice core from the Antarctic, though the signal was less striking because of the lower time resolution (several years); another smaller increase was seen in Greenland. When data from two sites in North Greenland and one in the West Antarctic, all taken with a one-year resolution, were compared they all showed a strong signal: the time profile also matched well with the 14C results (within the uncertainty of dating for the 10Be data). Chlorine-36 (36Cl, half-life 301 thousand years) can be produced from argon and deposited in polar ice; because argon is a minor atmospheric constituent the abundance is low. The same ice cores which showed 10Be also provided increases of 36Cl, though with a resolution of five years a detailed match was impossible.
A second event in AD 993/4 has also been found from 14C in tree rings, but at a lower intensity., and another event was found for 660 BCE This event also produced measurable increases in 10Be and 36Cl in Greenland ice cores.
If these events are presumed to be produced by energetic particles from large flares, it is not easy to estimate the particle energy in the flare or compare it with known events. The Carrington event does not appear in the cosmogenic records, and neither did any other large particle event that has been directly observed. The flux of particles must be estimated by calculating production rates of radiocarbon, and then modelling the behaviour of the CO2 once it has entered the carbon cycle; the fraction of the created radiocarbon taken up by trees depends to some extent on that cycle. The energetic particle spectrum of a solar flare varies considerably between events; one with a 'hard' spectrum, with more high-energy protons, will be more efficient at producing a 14C increase. The most powerful flare which also had a hard spectrum that has been observed instrumentally took place in February 1956 (the beginning of nuclear testing obscures any possible effects in the 14C record); it has been estimated that if a single flare were responsible for the AD 774/5 event it would need to be 25-50 times more powerful than this. One active region on the Sun may produce several flares over its lifetime, and the effects of such a sequence would be aggregated over the one-year period covered by a single 14C measurement; however, the total effect would still be ten times greater than anything observed in a similar period in modern times.
Solar flares are not the only possibility for producing the cosmogenic isotopes. A long or short gamma-ray burst has been initially proposed as a possible cause of the AD 774/5 event. However, this explanation turned out to be very unlikely, and the current paradigm is that these events are caused by extreme solar particle events.
Historical records.
A number of attempts have been made to find additional evidence supporting the superflare interpretation of the isotope peak around AD 774/5 by studying historical records. The Carrington event produced auroral displays as far south as Caribbean and Hawaii, corresponding to geomagnetic latitude of about 22°; if the event of 774/5 corresponded to an even more energetic flare there should have been a global auroral event.
Usoskin et al. cited references to aurorae in Chinese chronicles for AD 770 (twice), 773 and 775. They also quote a "red cross" in the sky in AD 773, 774, or 776 from the Anglo-Saxon Chronicle; "inflamed shields" or "shields burning with a red colour" seen in the sky over Germany in AD 776 recorded in the Royal Frankish Annals; "fire in heaven" seen in Ireland in AD 772; and an apparition in Germany in AD 773 interpreted as riders on white horses. The enhanced solar activity around the 14C increase is confirmed by the Chinese auroral record on AD 776 January 12, as detailed by Stephenson et al. The Chinese records describe more than ten bands of white lights "like the spread silk" stretching across eight Chinese constellations; the display lasted for several hours. The observations, made during the Tang dynasty, were made from the capital Chang'an.
Nevertheless, there are a number of difficulties involved when trying to link the 14C results to historical chronicles. Tree ring dates may be in error because there is no discernible ring for a year (unusually cold weather), or two rings (a second growth during a warm autumn). If the cold weather were global, following a large volcanic eruption, it is conceivable that the effects could also be global: the apparent 14C date may not always match the chronicles.
For the isotope peak in AD 993/994 studied by Hayakawa et al. surveyed contemporary historical documents show clustering auroral observations in late 992, while their relationship with the isotope peak is still under discussion.
General solar activity in the past.
Superflares seem to be associated with a general high level of magnetic activity. As well as looking for individual events, it is possible to examine the isotope records to find the activity level in the past and identify periods when it may have been much higher than now. Lunar rocks provide a record unaffected by geomagnetic shielding and transport processes. Both non-solar cosmic rays and solar particle events can create isotopes in rocks, and both are affected by solar activity. The cosmic rays are much more energetic and penetrate more deeply, and can be distinguished from the solar particles which affect the outer layers. Several different radioisotopes can be produced with very different half-lives; the concentration of each may be regarded as representing an average of particle flux over its half-life. Since fluxes must be converted into isotope concentrations by simulations there is a certain model-dependence here. The data are consistent with the view that the flux of energetic solar particles with energies above a few tens of MeV has not changed over periods ranging from five thousand to five million years. Of course, a period of intense activity over a time scale short with respect to the half-life would not be detected.
14C measurements, even with low time resolution, can indicate the state of solar activity over the last 11,000 years until about 1900. Although radiocarbon dating has been applied as far back as 50,000 years, during the deglaciations at the start of the Holocene the biosphere and its carbon uptake changed dramatically making estimation before this impractical; after about 1900 the Suess effect and nuclear bomb-tests makes interpretation difficult. 10Be concentrations in stratified polar ice cores provide an independent measure of activity. Both measures agree reasonably with each other and with the Zurich sunspot number of the last two centuries. As an additional check, it is possible to recover the isotope Titanium-44 (44Ti, half-life 60 years) from meteorites; this provides a measurement of activity that is not affected by changes in transport process or the geomagnetic field. Although it is limited to about the last two centuries, it is consistent with all but one of the 14C and 10Be reconstructions and confirms their validity. The energetic flare events discussed above are rare; on long time scales (significantly more than a year), the radiogenic particle flux is dominated by cosmic rays. The inner solar system is shielded by the general magnetic field of the sun, which is strongly dependent on the time within a cycle and the strength of the cycle. The result is that times of powerful activity show up as "decreases" in the concentrations of all these isotopes. Because cosmic rays are also influenced by the geomagnetic field, difficulties in reconstructing this field set a limit to the accuracy of the reconstructions.
The 14C reconstruction of activity over the last 11,000 years shows no period significantly higher than the present; in fact, the general level of activity in the second half of the 20th century was the highest since 9000 BC. In particular, the activity in the period around the AD 774 14C event (averaged over decades) was somewhat lower than the long-term average, while the AD 993 event coincided with a small minimum. A more detailed scrutiny of the period AD 731 to 825, combining several 14C datasets of one- and two-year resolution with auroral and sunspot accounts does show a general increase in solar activity (from a low level) after about AD 733, reaching its highest level after 757 and remaining high in the 760s and 770s; there were several aurorae around this time, and even a low-latitude aurora in China.
Effects of a hypothetical solar superflare.
The effect of the sort of superflare apparently found on the original nine candidate stars would be catastrophic for the Earth and would cause serious damage to the atmosphere and to life. Although it would not be nearly as powerful as a gamma ray burst. It also would leave traces on the Solar System; the event on S Fornacis for example involved an increase in the stars' luminosity by a factor of about twenty. Thomas Gold suggested that the glaze on the top surface of certain lunar rocks might be caused by a solar outburst involving a luminosity increase of over a hundred times for 10 to 100 seconds at some time in the last 30,000 years. Apart from the terrestrial effects, this would cause local ice melting followed by refreezing as far out as the moons of Jupiter. There is no evidence of superflares on this scale having occurred in the Solar System.
Even for much smaller superflares, at the lower end of the Kepler range, the effects would be serious. In 1859 the Carrington event caused failures in the telegraph system in Europe and North America. Possible consequences today would include:
It is evident that superflares often repeat rather than occurring as isolated events. The nitric oxide (NO) and other odd nitrogen compounds created by flare particles catalyse the destruction of ozone without being consumed themselves, and have a long lifetime in the stratosphere. Flares at a frequency of one a year or even less would have a cumulative effect; the destruction of the ozone layer could be permanent and lead to at least a low-level extinction event.
Superflares have also been suggested as a solution to the Faint young Sun paradox.
Can superflares occur on the Sun?
Since superflares can occur on stars apparently equivalent in every way to the Sun, it is natural to ask if they can occur on the Sun itself. An estimate based on the original Kepler photometric studies suggested a frequency on solar-type stars (early G-type and rotation period more than 10 days) of once every 800 years for an energy of 1034 erg and every 5000 years at 1035 erg. One-minute sampling provided statistics for less energetic flares and gave a frequency of one flare of energy 1033 erg every 500 to 600 years for a star rotating as slowly as the Sun; this would be rated as X100 on the solar flare scale. This is based on a straightforward comparison of the number of stars studied with the number of flares observed. An extrapolation of the empirical statistics for solar flares to an energy of 1035 erg suggests a frequency of one in 10,000 years.
However, this does not match the known properties of superflare stars. Such stars are extremely rare in the Kepler data; one study showed only 279 such stars in 31,457 studied, a proportion below 1%; for older stars this fell to 0.25%. Also, about half of the stars which were active showed repeating flares: one had as many as 57 events in 500 days. Concentrating on solar-type stars, the most active averaged one flare every 100 days; the frequency of superflare occurrence in the most active Sun-like stars is 1000 times larger than that of the general average for such stars. This suggests that such behaviour is not present throughout a star's lifetime, but is confined to episodes of extraordinary activity. This is also suggested by the clear relation between the magnetic activity of a star and its superflare activity; in particular, superflare stars are much more active (based on starspot area) than the Sun.
There is no evidence for any flare greater than the one observed by Carrington in 1859 and the November 2003 flare from active region 10486 (both about 4×1032 erg, or 1/2,000 of the largest superflares) in the last 200 years. Although larger events from the 14C record ca. 775 AD is unambiguously identified as a solar event, its association to the flare energy is unclear, and it is unlikely to exceed 1032 erg.
The more energetic superflares seem to be ruled out by energetic considerations for our sun, which suggest it is not capable of a flare of more than 1034 ergs. A calculation of the free energy in magnetic fields in active regions that could be released as flares gives an upper limit of around 3×1032 erg suggesting the most energetic a super flare can be is about that of the Carrington event.
Some stars have a magnetic field 5 times that of the Sun and rotate much faster and these could theoretically have a flare of up to 1034 ergs. This could explain some superflares at the lower end of the range. To go higher than this may require an anti-solar rotation curve - one in which the polar regions rotate faster than the equatorial regions.


Central massive object

Central massive object (CMO) refers to a mass concentration at the center of a galaxy. It can be either a supermassive black hole or a nuclear star cluster.
The most massive galaxies are thought to always contain a supermassive black hole (SBH); these galaxies do not contain nuclear star clusters, and the CMO is identified with the SBH. Fainter galaxies usually contain a nuclear star cluster (NSC). In most of these galaxies, it is not known whether a supermassive black hole is present, and the CMO is identified with the NSC. A few galaxies, for instance the Milky Way and NGC 4395, are known to contain both a SBH and a NSC.
The mass associated with CMOs is roughly 0.1–0.3% times the total mass of the galactic bulge.


Unafraid of the Dark

"Unafraid of the Dark" is the thirteenth and final episode of the American documentary television series ' and its series finale. It premiered on June 8, 2014, on Fox and aired on June 9, 2014, on the National Geographic Channel. The episode was written by Ann Druyan and Steven Soter, and directed by Ann Druyan, making this her series directorial debut. The episode explores the mysteries of dark energy and dark matter, as well as the contributions and theories of Swiss astronomer Fritz Zwicky, who furthered our understanding of "supernovae, neutron stars and 'standard candles.'" The finale reveals a recording of life on Earth - the final message on the golden record of the space probe, Voyager. The episode ends with Carl Sagan's (host of the original ') iconic speech on Earth as the "Pale Blue Dot."
Episode summary.
Tyson begins the episode by noting how the destruction of the Library of Alexandria lost much of humanity's knowledge to that point. He then contrasts on the strive for humanity to continue to discover new facts about the universe and the need to not close off further discovery.
Tyson then proceeds to describe the discovery of cosmic rays by Victor Hess through high-altitude balloon trips, where radiation increased the farther one was from the surface. Swiss Astronomer Fritz Zwicky, in studying supernovae, postulated that these cosmic rays originated from these events instead of electromagnetic radiation. Zwicky would continue to study supernovae, and by looking at standard candles that they emitted, estimated the movement of the galaxies in the universe. His calculations suggested that there must be more mass in the universe than those apparent in the observable galaxies, and called this dark matter. Initially forgotten, Zwicky's theory was confirmed by the work of Vera Rubin, who observed that the rotation of stars at the edges of observable galaxies did not follow expected rotational behavior without considering dark matter. This further led to the discovery of dark energy by Edwin Hubble to account for the known rate of expansion of the universe beyond the visible and dark matter mass.
Tyson then describes the interstellar travel, using the two "Voyager" probes. Besides the abilities to identify several features on the planets of the solar system, "Voyager I" was able to recently demonstrate the existence of the Sun's variable heliosphere which help buffer the Solar System from interstellar winds. Tyson describes Carl Sagan's role in the "Voyager" program, including creating the Voyager Golden Record to encapsulate humanity and Earth's position in the universe, and convincing the program directors to have "Voyager I" to take a picture of Earth from beyond the orbit of Neptune, creating the image of the Pale Blue Dot. Tyson concludes the series by emphasizing Sagan's message on the human condition in the vastness of the cosmos, and to encourage viewers to continue to explore and discover what else the universe has to offer.
The series concludes with the empty-seated Ship of the Imagination leaving Earth and traveling through space as Tyson looks on from planet Earth.
Reception.
The episode received a 1.1/3 in the 18-49 rating/share, with 3.09 million American viewers watching on Fox.


George Francis Hardy

Sir George Francis Hardy (14 December 1855 – 5 October 1914) was a British actuary, Egyptologist and amateur astronomer. He became a Fellow of the Royal Astronomical Society in 1877 and was President of the Institute of Actuaries from 1908 to 1910.
Career.
Aged 15, Hardy joined the British Mutual Empire Life Office and later qualified for the Institute of Actuaries, after passing his first exam in 1874 and becoming a Fellow in 1880. In that year he published (with George King) "Notes on the practical application of Mr Makeham's Formula to the Graduation of Mortality Tables" in which both practical methods and the theory of actuarial science were extended. This theory is now called the Gompertz–Makeham law of mortality.
Following years as a tutor and in private practice, Hardy was elected President of the Institute of Actuaries in 1908. He advised Governments, and was instrumental in the work that lead to the National Insurance Act 1911. A bronze bust of Hardy was sculpted by Gilbert Bayes for the institute. Hardy was a Chairman of the Actuarial Advisory Committee to the National Health Insurance Joint Committee, a role for which he was awarded the Order of the Bath in the 1914 New Year Honours.
He was made a Fellow of the Royal Astronomical Society on 9 February 1877. His interest in astronomy had started early, with a copy of Herschel's "Outlines of Astronomy" that was dated in his own hand when he was a teenager. In 1874, he suggested a new method of determining the Sun's distance from the Earth using solar parallax, which was published in "The English Mechanic and World of Science".
Hardy's interest in Egyptology led to suggesting a method for determining the age the Great Pyramid of Giza.
Based on astronomical evidence, he suggested that the Fourth Dynasty of Egypt would have started around 3,700 BC (now shown to be incorrect). This was between two other estimates: 2,700 to 2,840 (by various authorities) and 4,731 BC (by Flinders Petrie). Today the start of the Fourth Dynasty is dated to 2613 BC.
Personal life.
Hardy was born in Islington and died at Edwardes Square, Kensington, London, where he had lived. He was educated at a school at which his father was the head teacher.
He married Jane Ann Lester in 1883, who was a half sister of Muriel Lester.


Solar eclipse of February 5, 2065

A partial solar eclipse will occur on Thursday, February 5, 2065. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A partial solar eclipse occurs in the polar regions of the Earth when the center of the Moon's shadow misses the Earth.


Ernst K. Zinner

Ernst Kunibert Zinner (30 January 1937 – 30 July 2015) was an Austrian astrophysicist, known for his pioneering work in the analysis of stardust in the laboratory. He long had a position in the United States at the Laboratory for Space Physics (later part of the McDonnell Center for the Space Sciences) at Washington University in St. Louis, Missouri, where he had earned his doctorate. He came to the United States in the 1960s for graduate work. In addition, Zinner regularly taught at European universities, and other American institutions.
Personal life.
Zinner was born on 30 January 1937 at Steyr, Austria, a small town about 100 miles west of Vienna. Although his father, Kunibert Zinner, was a renowned sculptor, Ernst was more interested as a boy in nature and science. Zinner's four younger siblings, and other relatives, live in Austria.
While on sabbatical later in his career, he met Brigitte Wopenka, a faculty member of the Institute of Analytical Chemistry in Vienna. She returned with him to the United States and they married in 1980. They had a son, Max Giacobini Zinner. The son now lives in New York City.
Education and career.
Zinner obtained an undergraduate degree in physics from the Vienna University of Technology and started working. In the mid-1960s, he moved to St. Louis, Missouri to attend Washington University for graduate work. He earned his Ph.D. there in 1972 in high energy physics.
That year he was invited by Robert M. Walker to work at the Laboratory for Space Physics (later part of the McDonnell Center for the Space Sciences) at Washington University.
He also held positions at:
Zinner continued to work at the McDonnell Center for the Space Sciences for the rest of his career, in 1989 being named as a Research Professor of Physics and Earth and Planetary Sciences. He retired early in 2015.
Zinner was a member of the American Association for the Advancement of Science, the American Geophysical Union, and Sigma Xi. He was also a fellow of the American Physical Society, the Meteoritical Society, the Geochemical Society, and the European Association of Geochemistry.
Zinner had mantle cell lymphoma for the last 19 years of his life. He died on 30 July 2015 at the age of 78.
Research.
Zinner's PhD research was in high energy physics. He subsequently studied the effects that the environment within our solar system would have on the moon and the parent bodies of meteors, using nuclear particle tracks, micrometeoid craters, and elements in the solar wind. His later research was focused on the information contained in presolar grains carried by early meteorites. These grains were formed in atmospheres and explosions of stars outside of earth's solar system. They can provide information about the history of stellar nucleosynthesis and the formation of the solar system.
Zinner was instrumental in identifying, for the first time, material in meteorites that pre-dated the formation of the solar system 4.6 billion years ago. Zinner and his colleagues found minute amounts of stardust - diamond and silicon carbide - that originated outside the solar system.
Identification of these grains involved a measurement technique called secondary ion mass spectrometry (SIMS). Zinner was widely considered one of the leading authorities on the instrument, and he trained scientists worldwide in its use. The work led to the emergence of a new field of study, the laboratory analysis of stardust, which opened up new insights into the evolution of stars and nucleosynthesis of the elements.
Since 1974, Zinner's research has involved Ion microprobe analysis. He has worked with the Cameca IMS 3f instrument since 1982, and the Cameca NanoSIMS instrument since 2000. He led the Long Duration Exposure Facility.
Legacy.
After his death, his family established an "Ernst Zinner Scholarship Fund" to support advanced cello students in the Community Music School at Webster University. Zinner had started learning cello at age 55, along with his son, then age 4.


University of Oklahoma Observatory

University of Oklahoma Observatory (IAU code H30) is an astronomical observatory. It is located in Norman, Oklahoma on the campus of the University of Oklahoma.
Built in 1939, with a 10-inch Newtonian reflector and a smaller 3.5-inch telescope, it was housed in a 16-foot dome atop what was at the time the southernmost building on campus. In 1995, the original 10-inch telescope was replaced by a Meade SCT.


Elisabetta Pierazzo

Elisabetta "Betty" Pierazzo (1963-2011)  was a senior scientist at the Planetary Science Institute from 2002 to 2011. Pierazzo specialized in impact cratering. She was also an adjunct professor at the University of Arizona.
Life and career.
Elisabetta was born in Noale, Italy in 1963 to mother Maria Scattolin. In 1989, Pierazzo moved from her hometown to Tucson, Arizona and in 1990 began attending graduate school at the Department of Planetary Sciences division of the University of Arizona. She went on to receive her PhD in 1997 from the University of Arizona and was awarded the Gerard P. Kuiper Memorial Award for her work. From 1997 to 2002, Pierazzo stayed at the University of Arizona and served as a Research Associate. In 2007, Pierazzo married her husband Keith Powell. The same year, Pierazzo was promoted from research scientist to senior scientist at PSI.
In 2002, Pierazzo began work at the Planetary Science Institute as a research scientist, where she studied worked on meteoritic impacting modeling concerning early Earth, Mars, and Europa. Notably, Pierazzo worked on providing information about the Chicxulub impact, which is said to have killed the dinosaurs. In 2009, the scientist was featured in a three-part National Geographic special entitled "Known Universe", where she was interviewed about impact modeling at the Barringer meteor crater in Arizona. During this time, Pierazzo also served as adjunct faculty at the University of Arizona Lunar and Planetary Laboratory, where she taught Astrobiology. Pierazzo went on to coauthor a book entitled "Impact Cratering: Processes and Products" with coauthor Dr. Gordon Osinski. The book was published in 2012.
Death and afterward.
Pierazzo died of cancer on May 15, 2011 at the age of 47. A main-belt asteroid that was discovered in 1994 was dedicated posthumously to Pierazzo. In 2013, the Planetary Science Institute established an International Student Travel award in Pierazzo's honor, where students can apply to receive up to $2,000 in funding to help students in the United States pursue graduate work abroad, or American graduate students working abroad return. Additionally, a crater on the moon was also dedicated to the scientist in 2015. Finally, a school in Pierazzo's hometown of Noale was dedicated to her. The school serves as both an elementary and a middle school, teaching 6-9 and 10-12 year old students.


Nidia Morrell

Nidia Irene Morrell (born 3 July 1953) is an Argentine astronomer who is a permanent staff member at the Las Campanas Observatory in La Serena, Chile. She was a member of the Massive Stars research group led by Virpi Niemelä and the Hubble Heritage Project. Professionally, she is known for her numerous contributions related to the astrophysics of massive stars. She participates in the systematic search for variations of brightness in stellar objects, including the observation of a candidate for the Thorne–Żytkow object. She was also a member of the team that discovered the supernova ASASSN-15lh.
Career.
Nidia Morrell studied astronomy at the National University of La Plata (UNLP), obtaining a licentiate in 1977 and a doctorate in 1984. She received a postdoctoral fellowship (1989–1990) sponsored by the National Scientific and Technical Research Council (CONICET) to conduct research in the United States, advised by at the Kitt Peak National Observatory. Back in Argentina, she researched and taught at the UNLP Faculty of Astronomical and Geophysical Sciences.
She focused her work on young (mostly O-type and Wolf-Rayet) stars, in regions of star formation and binary stars of large masses, also called massive stars. That type of star quickly consumes its fuel, and ends its existence with a giant explosion: a supernova.
In La Plata, Morrell was a member of the Massive Stars research group led by Virpi Niemelä. She and Niemelä were part of the Hubble Heritage Project, which generated widely disseminated educational resources. From 1996 to 2001, Morrell was a representative of Argentina and a scientific advisor to the Gemini South Observatory.
For years she was one of the main users of the Jorge Sahade Telescope at the Leoncito Astronomical Complex (CASLEO). Many students, who are now astronomers and teachers, made their first observations with her at El Leoncito.
In late 2002, Morrell joined the scientific team at Las Campanas Observatory and, later, the Carnegie Supernova Project (as a part-time researcher), while continuing to collaborate on massive star studies. She was also a visiting professor at the National Autonomous University of Honduras and the National Autonomous University of Nicaragua.
In 2006 she settled in La Serena, Chile to continue her research. Among her most outstanding observations, she participated in the discovery of ASASSN-15lh, the brightest supernova ever detected.
Since 2008, Morrell has also participated in Chilean Observation Time Assignment Committees, contributing her knowledge about instruments and procedures for astronomical observation.
In 2009, she appeared in the documentary video "El silencio de las Campanas" made by Ricardo Benítez, which follows the daily activity of astronomers at a high-level observatory.
In 2014 she was one of the leaders in the detection of a possible hybrid star or Thorne–Żytkow object, which had been a theoretical postulate for years. This discovery involved the Magellan Telescopes. The chemical characteristics of this star, HV 2112, were studied using spectroscopy techniques, in which Morrell is an expert.
Beliefs.
Throughout her career, Morrell has motivated students of all ages to participate in scientific projects. She has also joined professional initiatives to raise awareness of respecting the sky as world heritage.
She is a staunch defender of the use of free software, free knowledge, and the equality and inclusion of all human beings. She has also collaborated with amateur astronomers who contribute to the search for supernovae from their homes.
Recognitions.
For her passion for astronomy, her dedication to mentoring students, and the enormous amount of observational data she has gathered, the international conference Massive Stars and Supernovae was held in celebration of her 65th birthday. The event took place from 5 to 9 November 2018 in Bariloche, Argentina, with the institutional support of the National University of Río Negro (UNRN), the UNLP Faculty of Astronomical and Geophysical Sciences, the , the Carnegie Institution for Science, and the Municipality of Bariloche.
Both for Dr. Morrell's scientific achievements and for her charisma, in the course of this meeting it was announced that the International Astronomical Union named an asteroid (Minor Planet 25906) in her honor.


Denise Stephens

Denise C. Nuttall Stephens is an associate professor of astronomy in the College of Physical and Mathematical Sciences in the Department of Physics and Astronomy at Brigham Young University.
Education and research experience.
Stephens graduated from Brigham Young University in 1996 as an undergraduate student with a degree in physics. She received her Master's and Ph.D. in Astronomy from New Mexico State University. She completed her a postgraduate program at the Space Telescope Science Institute and at Johns Hopkins University. She joined the faculty of BYU in 2007. She studies the atmosphere of brown dwarfs, looks for and classifies binary systems, studies TNOs, and uses telescopes both on ground and in space to collect infrared data.
In 2017, she and a team of undergraduates at BYU published their discovery of a new planet called KELT-16b, which was made as part of the KELT project.
Community involvement.
Stephens is a coordinator of the BYU Astronomical Society. She also runs an annual public event called Astrofest which introduces physics and astronomy to kids in a fun way. She is the team captain of an on-campus flag football team which is the only women's intramural faculty team at BYU.
Personal life.
Denise Stephens is married and is a mother to seven children.


Angell Hall Observatory

Angell Hall Observatory is an astronomical observatory owned and operated by University of Michigan. It is located on the UM Central Campus on top of Angell Hall in Ann Arbor, Michigan (US). It has a computer-controlled 0.4-m Cassegrain telescope in its single dome, and a small radio telescope on the roof. In the past it has housed a large, clock-driven refracting telescope and a reflecting telescope in side-by-side domes. The current telescope was manufactured by DFM Engineering and installed in December 1994.
Other observatories that UM has operated include the Detroit Observatory (1854), the Lamont-Hussey Observatory (South Africa, 1928), the McMath-Hulbert Observatory (Lake Angelus, Michigan, 1930), the Portage Lake Observatory (near Dexter, Michigan, 1948), and the Peach Mountain Observatory (near Dexter, Michigan, 1958).


Gloria Dubner

Gloria Dubner (born May 5, 1950) is an Argentinian astrophysicist and Director of the Instituto de Astronomía y Física del Espacio in Buenos Aires and a Senior Researcher at the National Scientific and Technical Research Council. She is known for her research on supernovas.
Education.
Dubner was born on May 5, 1950 in the city of Chajarí, located in the Entre Ríos Province in Argentina. She received her Licentiate degree in physics in 1974 from the University of Buenos Aires at the age of 23. She then attended National University of La Plata, where she received her PhD in physics in 1982 under the mentorship of astronomer and Guggenheim Fellow Fernando Raúl Colomb.
Research and career.
Career trajectory.
Between 1975 and 1987, Dubner worked at the Argentine Institute of Radio Astronomy. In 1988, she began working at the Instituto de Astronomía y Física del Espacio (IAFE). In 1997, she also was appointed as a researcher at the National Scientific and Technical Research Council, continuing her study of supernovas. In 2009, she became the Director of IAFE and also serves as the Director of the Supernovas and Interstellar Environment group.
Research contributions.
Dubner has participated in a number of international collaborations to study galactic supernova remnants. For instance, in 1994, she and her American collaborators Frank Winkler and W. Miller Gross were awarded a National Science Foundation grant to image the expanding shell of gas left over after a star explodes using data collected from radio telescopes in the US and Argentina.
Starting in 2015, Dubner also led a collaboration between five observatories that led to the production of the most detailed image produced of the Crab Nebula, a bright supernova explosion first observed by Chinese astronomers in 1054. The collaboration leveraged data collected at different wavelengths to create a composite image using: infrared data generated by the Spitzer Space Telescope from NASA's Jet Propulsion Laboratory, visible light data from the Hubble Space Telescope, ultraviolet data from the XMM-Newton operated by the European Space Agency, radio image and X-ray data from NASA's Chandra X-ray Observatory, and radio data from the Very Large Array operated by the National Radio Astronomy Observatory.
Leadership and recognition.
Dubner is an active member of the International Astronomical Union (IAU), serving on a variety of commissions including the Working Group for Historic Radio Astronomy, the Division for Interstellar Matter and Local Universe, and the Commission for Astrochemistry. In 2006, she served on the Organizing Committee to report advances in the field of radio astronomy between 2002 and 2005. In 2012, she was part of the organizing committee of the IAU's XXVIII General Assembly for Women in Astronomy Meeting. In June 2008, the minor planet 9515 Dubner was named in her honor, recognizing her achievements at the IAU. The planet was first discovered at the observatory in El Leoncito National Park in 1975.


Zytturm, Zug

The Zytturm is a 13th-century tower in Zug, Switzerland, which houses an astronomical clock. The tower, which is 52 metres high, is located on Kolinplatz in the old town centre.
The tower was constructed in the 13th century, then heightened between 1478 and 1480, taking its current form in 1557. The tower's last major renovation was in 1952. It is listed as being of National and Regional Significance, along with the city walls and other towers.
Astronomical clock.
The astronomical clock on the eastern side of the tower was installed in 1574. Underneath the clockface, the calendar dial has four hands:
Above the clockface, a rotating moon ball indicates the lunar phase.
Canton shields.
On the eastern side of the tower, below the clock, are displayed the coats of arms of the which comprised the Old Swiss Confederacy from 1353 to 1481.


Philip Morton

Philip Howard Morton (20 June 1857 – 13 May 1925) was an English cricketer and schoolmaster.
He played for Cambridge, the Gentlemen, Surrey, and Norfolk. In the heyday of his teaching career, he was head master of the fashionable prep school Wixenford from 1903 to 1918.
Life.
The second son of the Rev. E. H. Morton, and the younger brother of another first-class cricketer, C. H. Morton, the young Morton was educated at Rossall School and Trinity College, Cambridge. A right-arm fast bowler, he was a member of the famous Cambridge University team of 1878 which included A. P. Lucas, Alfred Lyttelton and his brother Edward, and A. G. Steel.
After Cambridge, Morton played for Surrey and the Gentlemen of England, and he retired from first-class cricket in 1886. He also played for Norfolk.
His career was as a schoolmaster, and he taught at Elstree School from 1880 to 1889, then was Head Master of Bracewell Hall, Skipton, from 1889 to 1896, of Scaitcliffe School, Englefield Green, from 1896 to 1903, and finally of Wixenford School, Wokingham, from 1903 to 1918.
He died on 15 May 1925 at Bournemouth, after an operation.


C/2020 F8 (SWAN)

C/2020 F8 (SWAN), or Comet SWAN, is an Oort cloud comet that was discovered in images taken by the Solar Wind Anisotropies (SWAN) camera on March 25, 2020, aboard the Solar Heliospheric Observer (SOHO) spacecraft. In the glare of twilight, Comet SWAN is difficult to find with 50mm binoculars even though it is still near the theoretical range of naked eye visibility. The comet has dimmed since May 3. As of perihelion, the comet is very diffuse, does not have a visible nucleus and is not a comet that will be noticed by inexperienced observers. It is likely that the comet disintegrated.
Observing.
It is from Earth in the constellation of Perseus and less than 25 degrees from the Sun. It has an apparent magnitude of 7 and is too diffuse to be visible to the naked eye even from a dark site. The comet is also hidden by the glare of twilight, zodiacal light and atmospheric extinction. It was originally best seen from the Southern Hemisphere. It was expected to possibly reach 3rd magnitude in May, but is now expected to hover closer to magnitude 6. Either way it will be near the glare of twilight. It passed through the celestial equator on 7 May, then it headed northward and it was near the 2nd magnitude star Algol on 20 May. In the Northern Hemisphere it might be best seen at the end of May when it is near the star Capella.
Orbit.
The Minor Planet Center initially listed the orbit as bound with formula_1. With a short 18-day observation arc JPL listed the comet as hyperbolic with an eccentricity of , but a longer observation arc was needed to refine the uncertainties and either confirm its hyperbolic trajectory, or determine its orbital period of thousands or millions of years. With a 40-day observation arc it is now known that it came from the Oort cloud on a Hyperbolic trajectory and that the outbound orbit will be ~11,000 years.
On May 12, 2020, the comet passed about from Earth. On May 27, 2020 the comet came to perihelion from the Sun.


Friedrich Bernhard Gottfried Nicolai

Friedrich Bernhard Gottfried Nicolai (October 25, 1793 – June 4, 1846) was a German astronomer.
Born in Braunschweig, Nicolai was educated at Göttingen. In 1812, he calculated the Euler–Mascheroni constant to 40 decimal places. In 1816, he joined the Mannheim observatory where he became the director.
The crater Nicolai on the Moon is named after him.


Solar eclipse of January 5, 2038

An annular solar eclipse will occur on January 5, 2038. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide.
Images.
Animated path
Related eclipses.
There are 7 eclipses in 2038 (the maximum possible), included four penumbral lunar eclipses: January 21, June 17, July 16, and December 11.


Some of the Things That Molecules Do

"Some of the Things That Molecules Do" is the second episode of the American documentary television series ". It premiered on March 16, 2014 on Fox.
The episode received positive reviews, with critics praising the beautiful graphics as well as the wonder-inspiring and straightforward narrative of how evolution works. Despite positive reviews, however, the episode received a 2.0/5 in the 18-49 rating/share, with 4.95 million American viewers watching it live—a decrease from the 5.77 million viewers who watched the series premiere.
Episode summary.
The episode covers several facets of the origin of life and evolution. Tyson describes both artificial selection via selective breeding, using the example of mankind's domestication of wolves into dogs, and natural selection that created species like polar bears. Tyson uses the Ship of the Imagination to show how DNA, genes, and mutation work, and how these led to the diversity of species as represented by the Tree of Life, including how complex organs such as the eye came about as a common element.
Tyson describes extinction of species and the five great extinction events that wiped out numerous species on Earth, while some species, such as the tardigrade, were able to survive and continue life. Tyson speculates on the possibility of life on other planets, such as Saturn's moon, Titan, as well as how abiogenesis may have originated life on Earth. The episode concludes with an animation from the original " showing the evolution of life from a single cell to mankind today, with music from Vivaldi's Mandolin Concerto.
Reception.
Upon airing on Fox, the episode received a 2.0/5 in the 18-49 rating/share, with 4.95 million American viewers watching it live. It placed fourth and last in its timeslot behind "Resurrection", "The Good Wife", and "Believe"; and twelfth out of sixteen for the night.


Palomar Observatory

Palomar Observatory is an astronomical research observatory in San Diego County, California, United States, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observatory is granted to Caltech and its research partners, which include the Jet Propulsion Laboratory (JPL), Yale University, and the National Optical Observatories of China.
The observatory operates several telescopes, including the 200-inch () Hale Telescope, the 48-inch () Samuel Oschin Telescope, and the Palomar 60-inch (1.5-m) Telescope. In addition, other instruments and projects have been hosted at the observatory, such as the Palomar Testbed Interferometer and the historic 18-inch () Schmidt telescope, Palomar Observatory's first telescope, dating from 1936. As of 2021, the observatory also hosts the Zwicky Transient Facility (ZTF) and Gattini-IR projects.
History.
Hale's vision for large telescopes and Palomar Observatory.
Astronomer George Ellery Hale, whose vision created the Palomar Observatory, built the world's largest telescope four times in succession. He published a 1928 article proposing what was to become the 200-inch Palomar reflector; it was an invitation to the American public to learn about how large telescopes could help answer questions relating to the fundamental nature of the universe. Hale followed this article with a letter to the International Education Board (later absorbed into the General Education Board) of the Rockefeller Foundation dated April 16, 1928 in which he requested funding for this project. In his letter, Hale stated:
"No method of advancing science is so productive as the development of new and more powerful instruments and methods of research. A larger telescope would not only furnish the necessary gain in light space-penetration and photographic resolving power, but permit the application of ideas and devices derived chiefly from the recent fundamental advances in physics and chemistry."
Hale Telescope.
The 200-inch telescope is named after astronomer and telescope builder George Ellery Hale. It was built by Caltech with a $6 million grant from the Rockefeller Foundation, using a Pyrex blank manufactured by Corning Glass Works under the direction of George McCauley. Dr. J.A. Anderson was the initial project manager, assigned in the early 1930s. The telescope (the largest in the world at that time) saw first light January 26, 1949 targeting NGC 2261. The American astronomer Edwin Powell Hubble was the first astronomer to use the telescope.
The 200-inch telescope was the largest telescope in the world from 1949 until 1975, when the Russian BTA-6 telescope saw first light. Astronomers using the Hale Telescope have discovered distant objects called quasars (a subset of what was to become known as Active Galactic Nuclei) at cosmological distances. They have studied the chemistry of stellar populations, leading to an understanding of the stellar nucleosynthesis as to origin of elements in the universe in their observed abundances, and have discovered thousands of asteroids. A one-tenth-scale engineering model of the telescope at Corning Community College in Corning, New York, home of the Corning Glass Works (now Corning Incorporated), was used to discover at least one minor planet, 34419 Corning.
Architecture and design.
Russell W. Porter developed the Art Deco architecture of the Observatory's buildings, including the dome of the 200-inch Hale Telescope. Porter was also responsible for much of the technical design of the Hale Telescope and Schmidt Cameras, producing a series of cross-section engineering drawings. Porter worked on the designs in collaboration with many engineers and Caltech committee members.
Max Mason directed the construction and Theodore von Karman was involved in the engineering.
Palomar Observatory and light pollution.
Much of the surrounding region of Southern California has adopted shielded lighting to reduce the light pollution that would potentially affect the observatory.
Research.
Palomar Observatory remains an active research facility, operating multiple telescopes every clear night, and supporting a large international community of astronomers who study a broad range of research topics.
The Hale Telescope remains in active research use and operates with a diverse instrument suite of optical and near-infrared spectrometers and imaging cameras at multiple foci. The Hale also operates with a multi-stage, high-order adaptive optics system to provide diffraction-limited imaging in the near-infrared. Key historical science results with the Hale include cosmological measurement of Hubble Flow, the discovery of quasars as the precursor of Active Galactic Nuclei, and studies of stellar populations and stellar nucleosynthesis.
The Oschin and 60-inch telescopes operate robotically and together are support a major transient astronomy program, the Zwicky Transient Facility.
The Oschin was created to facilitate astronomical reconnaissance, and has been used in many notable astronomical surveys—among them are:
POSS-I.
The initial Palomar Observatory Sky Survey (POSS or POSS-I), sponsored by the National Geographic Institute, was completed in 1958. The first plates were exposed in November 1948 and the last in April 1958. This survey was performed using 14 inch2 (6 degree2) blue-sensitive (Kodak 103a-O) and red-sensitive (Kodak 103a-E) photographic plates on the Oschin Telescope. The survey covered the sky from a declination of +90 degrees (celestial north pole) to −27 degrees and all right ascensions and had a sensitivity to +22 magnitudes (about 1 million times fainter than the limit of human vision). A southern extension extending the sky coverage of the POSS to −33 degrees declination was shot in 1957–1958. The final POSS I dataset consisted of 937 plate pairs.
Digitized Sky Survey (DSS) produced images which were based on the photographic data developed in the course of POSS-I.
J.B. Whiteoak, an Australian radio astronomer, used the same instrument to extend POSS-I data south to -42 deg declination. Whiteoak's observations used using the same field centers as the corresponding northern declination zones. Unlike POSS-I, the Whiteoak extension consisted only of red-sensitive (Kodak 103a-E) photographic plates.
POSS-II.
The Second Palomar Observatory Sky Survey (POSS II, sometimes Second Palomar Sky Survey) was performed in the 1980s and 1990s and made use of better, faster films and an upgraded telescope. The Oschin Schmidt was upgraded with an achromatic corrector and provisions for autoguiding. Images were recorded in three wavelengths: blue (IIIaJ. 480 nm), red (IIIaF, 650 nm) and near infrared (IVN, 850 nm) plates, respectively. Observers on POSS II included C. Brewer, D. Griffiths, W. McKinley, J. Dave Mendenhall, K. Rykoski, Jeffrey L. Phinney and Jean Mueller (who discovered over 100 supernovae by comparing the POSS I and POSS II plates). Mueller also discovered several comets and minor planets during the course of POSS II, and the bright Comet Wilson 1986 was discovered by then graduate student C. Wilson early in the survey.
Until the completion of the Two Micron All Sky Survey (2MASS), POSS II was the most extensive wide-field sky survey. When completed, the Sloan Digital Sky Survey will surpass POSS I and POSS II in depth, although the POSS covers almost 2.5 times more area on the sky.
POSS II also exists in digitized form (i.e., the photographic plates were scanned) as part of the Digitized Sky Survey (DSS).
QUEST.
The multi-year POSS projects were followed by the Palomar Quasar Equatorial Survey Team (QUEST) Variability survey. This survey yielded results that were used by several projects, including the Near-Earth Asteroid Tracking project. Another program that used the QUEST results discovered 90377 Sedna on 14 November 2003, and around 40 Kuiper belt objects. Other programs that share the camera are Shri Kulkarni's search for gamma-ray bursts (this takes advantage of the automated telescope's ability to react as soon as a burst is seen and take a series of snapshots of the fading burst), Richard Ellis's search for supernovae to test whether the universe's expansion is accelerating or not, and S. George Djorgovski's quasar search.
The camera for the Palomar QUEST Survey was a mosaic of 112 charge-coupled devices (CCDs) covering the whole (4 degree by 4 degree) field of view of the Schmidt telescope. At the time it was built, it was the largest CCD mosaic used in an astronomical camera. This instrument was used to produce The Big Picture, the largest astronomical photograph ever produced. The Big Picture is on display at Griffith Observatory.
Current research.
Current research programs on the 200-inch Hale Telescope cover the range of the observable universe, including studies on near-Earth asteroids, outer Solar System planets, Kuiper Belt objects, star formation, exoplanets, black holes and x-ray binaries, supernovae and other transient source followup, and quasars/Active Galactic Nuclei.
The 48-inch Samuel Oschin Schmidt Telescope operates robotically, and supports a new transient astronomy sky survey, the Zwicky Transient Facility (ZTF).
The 60-inch telescope operates robotically, and supports ZTF by providing rapid, low-dispersion optical spectra for initial transient classification using the for-purpose Spectral Energy Distribution Machine (SEDM) integral field spectrograph.
Visiting & Public Engagement.
Palomar Observatory is an active research facility. However, selected observatory areas are open to the public during the day. Visitors can take self-guided tours of the 200-inch telescope daily from 9 a.m. to 3 p.m. The observatory is open 7 days a week, year round, except for December 24 and 25 and during times of inclement weather, and for now, global pandemic. Guided tours of the 200-inch Hale Telescope dome and observing area are available Saturdays and Sundays from April through October. Behind-the-scenes tours for the public are offered through the community support group, Palomar Observatory Docents.
Palomar Observatory also has an on-site museum—the Greenway Visitor Center containing observatory and astronomy-relevant exhibits, a gift shop, and hosts periodic public events.
For those unable to travel to the observatory, Palomar provides an extensive virtual tour that provides virtual access to all the major research telescopes on-site, the Greenway Center, and has extensive embedded multimedia to provide additional context. Similarly the observatory actively maintains an extensive website and YouTube channel to support public engagement.
The observatory is located off State Route 76 in northern San Diego County, California, two hours' drive from downtown San Diego and three hours' drive from central Los Angeles ( UCLA, LAX airport ). Those staying at nearby Palomar Campground can visit Palomar Observatory by hiking up Observatory Trail.


Institute for Astronomy (Hawaii)

The Institute for Astronomy (IfA) is a research unit within the University of Hawaii system, led by Robert McLaren as Acting Director. IfA main headquarters are located at 2680 Woodlawn Drive in Honolulu, Hawaii, , adjacent to the University of Hawaii at Mānoa campus. Additional facilities are located at Pukalani, Maui and Hilo on Hawaii island (the Big Island). IfA employs over 150 astronomers and support staff. IfA astronomers perform research into Solar System objects, stars, galaxies and cosmology.
The Institute for Astronomy was founded in 1967 to conduct research and to manage the observatory complexes at Haleakalā, Maui and the Mauna Kea Observatory on the summit of Mauna Kea. It has approximately 55 faculty and employs over 300 people.


Franz von Gruithuisen

Baron
Franz von Paula (Franciscus de Paula) Gruithuisen (March 19, 1774 – June 21, 1852) was a Bavarian physician and astronomer. He taught medical students before becoming a professor of astronomy at the University of Munich in 1826.
During his period of medical studies and instruction, he was noted for his contributions to urology and lithotripsy. He developed ideas on safer methods to remove bladder stones transurethrally, and his instruments served as models for subsequent devices.
Like others before and since his time, Gruithuisen believed that the Earth's Moon was habitable. He made multiple observations of the lunar surface that supported his beliefs, including his announcement of the discovery of a city in the rough terrain to the north of Schröter crater he named the "Wallwerk". This region contains a series of somewhat linear ridges that have a fishbone-like pattern, and, with the small refracting telescope he was using, could be perceived as resembling buildings complete with streets. He published his observations in 1824, but they were greeted with much skepticism by other astronomers of the time. His claims were readily refuted using more powerful instruments. Gruithuisen was also the first to suggest that craters on the Moon were caused by meteorite impacts.
He is also noted for the discovery of bright caps on the cusps of the crescent Venus, which he attempted to explain by proposing that jungles on Venus grew more rapidly than in Brazil due to the proximity of the planet to the Sun, and that as a consequence the planet's inhabitants celebrated fire festivals during which they burned massive amounts of vegetation.
Gruithuisen lived at 24 Brienner Straße in Munich shortly before his death. The crater Gruithuisen on the Moon is named for him.
Bibliography.
Baron von Gruithuisen was noted for his prolific rate of publication.


HST events

HST events, things of interest related to the Hubble Space Telescope, chronologically.


Johnstown (meteorite)


Laura A. Lopez

Laura A. Lopez is an assistant professor of astronomy at Ohio State University studying the life cycle of stars. She was awarded the Annie Jump Cannon Award in Astronomy in 2016, which is awarded by the American Astronomical Society (AAS) for outstanding research and promise for future research by a postdoctoral woman researcher.
Early life and education.
Lopez is originally from Barrington, Illinois, a northwest suburb of Chicago, and graduated from Barrington High School in 2000. She received her undergraduate degree from Massachusetts Institute of Technology in 2004. Lopez earned her PhD in astronomy and astrophysics from the University of California Santa Cruz in 2011. After completing her PhD she was an Einstein Fellow and Pappalardo Fellow in Physics at Massachusetts Institute of Technology (2011-2014). Following that, she was a Hubble Fellow at the Harvard-Smithsonian Center for Astrophysics (2014-2015).
Career.
Lopez has contributed to the field of the life cycle of stars. She has used the NuSTAR X-ray satellite to study Tycho's Supernova remnant. Using optical, infrared, radio, and X-ray images, she measured the pressures exerted on the remnant shells from direct stellar radiation, dust-processed radiation, warm ionized gas, and hot X-ray-emitting gas.
Lopez has used data acquired from various observatories to show that Supernova Remnant (SNR) 0104–72.3 in the Small Magellanic Cloud arose from a jet-driven bipolar core-collapse supernova.
Using the Advanced CCD Imaging Spectrometer on board the Chandra X-ray Observatory, Lopez observed the Galactic supernova remnant (SNR) W49B to understand the thermodynamic properties and explosive origin of the SNR. The observed electron temperature and absorbing column toward W49B suggest that the mean metal abundances are consistent with the predicted yields in models of bipolar/jet-driven core-collapse SNe. W49B is thus likely a bipolar Type Ib/Ic SN, making it the first of its kind to be discovered in the Milky Way.
Lopez is interested in diversity in astronomy and is an advocate of the LGBTIQ astronomical community. Additionally, she has previously served on the AAS Committee on the Status of Minorities in Astronomy (CSMA).


X-ray flash (astronomy)

In astronomy, an X-ray flash is a transient emission of X-rays originating in a distant galaxy, probably caused by a hypernova. They have been observed to last 90 to 200 seconds.
Nearly all hypernovae are detected via (higher-energy) gamma-ray photons, at distances too great for any associated X-ray emissions from them to be observed; nevertheless, the two main theories of the nature of an X-ray flash each assume that a hypernova is involved:


Merivale Molyneux

Frederick Merivale Molyneux (called Merivale; 10 May 188520 November 1948) was a British Anglican bishop who served as Bishop of Melanesia.
Family and education.
Born at Bransgore, Molyneux was the son of Rosa and Frederick Molyneux (a priest) and grandson of lawyer Echlin Molyneux; he was younger brother to Ernest, also a priest, who served as his commissary in Britain (1928–1932). Merivale was educated at Rossall School, and Keble College, Oxford (he graduated Bachelor of Arts {BA} in 1908 and proceeded Master of Arts (Oxford) {MA Oxon} in 1913), and trained for the ministry at Cuddesdon College.
Early ministry.
He was made deacon at Advent 1909 (18 December) and ordained priest at Lent 1911 (12 March) — both times by William Boyd Carpenter, Bishop of Ripon, at Ripon Cathedral. His title (curacy) was of All Souls' Leeds, until 1913, when he returned to Cuddesdon as college Chaplain. During this time (the Great War), he was also a Chaplain to the Forces (CF) in Mesopotamia (1916–19): for which he was mentioned in despatches, made a Member of the Order of the British Empire (3 June 1918) and an honorary chaplain to the forces (Hon CF) in 1919. He had been in Mesopotamia for 3 years other than for 6 months leave in 1918 spent in Ceylon. He had spent much of his commission working in hospitalsHe served as Vicar of High Wycombe from 1920.
Melanesia.
On 14 July 1924, the Melanesian Mission committee in England recommended Molyneux to the New Zealand bishops and John Steward, Bishop of Melanesia, for appointment as an assistant bishop of that diocese; by April 1925, when Thomas Strong, Bishop of Oxford, presented him with a crozier at High Wycombe, that recommendation had been accepted, and he was duly consecrated a bishop on 9 August 1925 by Alfred Averill, Archbishop of New Zealand in St Paul's Pro-Cathedral, Wellington. Molyneux then served as Assistant Bishop of Melanesia from 1925 to 1928: initially, he had responsibility for the Southern Archdeaconery (based in Lolowai, Aoba (now called Ambae), but lived primarily in the Banks Islands; however, as Steward's health declined, Molyneux increasingly assisted him throughout the diocese.
Steward having announced his imminent resignation (due to ill-health), on 13 June 1928 the diocesan synod unanimously chose to nominate Molyneux for the diocesan See; Steward having resigned effective 1 August, the New Zealand bishops elected Molyneux on 16 August, and he was enthroned at St Luke's Cathedral, Siota on 13 November. His assistant bishop Edward Wilton having resigned 1 July 1929, Molyneux he wrote to the Mission committee on 8 October 1930 to ask for a new assistant bishop; in 1931, John Dickinson became assistant bishop for the Southern area.
Return to Britain.
In the midst of allegations of "improper conduct with young men" and "concerns about erotic involvements with men", he experienced a "complete nervous breakdown", resigned his See in November 1931, and left the Solomon Islands. He arrived back in Britain in January 1932, where he retired to Hampshire — initially with his father at Martyr Worthy rectory. Cyril Garbett, Bishop of Winchester, declined to licensed the younger Molyneux to any ministry; he became a farmer. He died at the Royal Victoria Hospital, Boscombe and was buried at Bransgore.


Arne Henden

Arne Henden is a retired American observational astronomer, instrument and software specialist, and co-discoverer of a minor planet. He formerly served as Director of the American Association of Variable Star Observers (AAVSO). The asteroid 33529 Henden is named after him.
Early life.
Henden was born in Huron, South Dakota, but as the son of an engineer in the U.S. Army Corps of Engineers, he would call several places home as he grew up with his parents and two sisters. His first astronomical brush happened when he had a chance to look at Saturn through the 24" Clarke refractor at the Lowell Observatory in Flagstaff, Arizona.
Henden gained his Bachelor of Science in Astrophysics in 1972, and his Masters in Physics in 1975 both from the University of New Mexico in Albuquerque. In 1978 he continued to gain a Masters of Science in 1978 and a Ph.D. in 1985 in Astronomy, both from the Indiana University Bloomington.
Work.
Henden moved to Ohio State University to work on the Large Binocular Telescope after gaining his doctorate. He also built several imagers and spectrographs for the 1.8-meter Perkins telescope.
in 1992, he returned to work at the United States Naval Observatory Flagstaff Station (NOFS) as a Senior Research Scientist, the site where his love for astronomy first started. At NOFS, he specialized in visual and near-IR imaging systems and co-discovered 239046 Judysyd, a faint asteroid of the main-belt, in collaboration with astronomer Stephen Levine on 25 February 2006. Henden was also part of the team that created specifications for the Discovery Channel's 4.2m telescope. He has also worked on the Sloan Digital Sky Survey and consulted for the Radio Astronomy Institute in developing a robotic observatory near the Grand Canyon.
In the Spring of 2004, Henden was named Director of the American Association of Variable Star Observers (AAVSO), an organization he had long been a member of.
Henden has authored more than 100 articles in peer-reviewed publications as either primary or co-author. Henden has also positioned himself as a specialist in photometry by writing one of the classic texts in the subject: "Astronomical Photometry" (1978: Willman-Bell) Henden has worked extensively with amateurs interested in variable stars and minor planet astrometry mainly through the AAVSO.
Awards and honors.
He was elected a Legacy Fellow of the American Astronomical Society in 2020.
33529 Henden, a main-belt asteroid discovered by American amateur astronomer Charles Juels in 1999, was officially named in his honor by IAU's Minor Planet Center on 18 September 2005 ().