Discovery and naming.

Europa, along with Jupiter's three other large moons, Io, Ganymede, and Callisto, was discovered by Galileo Galilei on 8 January 1610, and possibly independently by Simon Marius. The first reported observation of Io and Europa was made by Galileo on 7 January 1610 using a 20×-magnification refracting telescope at the University of Padua. However, in that observation, Galileo could not separate Io and Europa due to the low magnification of his telescope, so that the two were recorded as a single point of light. The following day, 8 January 1610 (used as the discovery date for Europa by the IAU), Io and Europa were seen for the first time as separate bodies during Galileo's observations of the Jupiter system.  Europa is named after Europa, daughter of the king of Tyre, a Phoenician noblewoman in Greek mythology. Like all the Galilean satellites, Europa is named after a lover of Zeus, the Greek counterpart of Jupiter. Europa was courted by Zeus and became the queen of Crete. The naming scheme was suggested by Simon Marius, who attributed the proposal to Johannes Kepler.  The names fell out of favor for a considerable time and were not revived in general use until the mid-20th century. In much of the earlier astronomical literature, Europa is simply referred to by its Roman numeral designation as "" (a system also introduced by Galileo) or as the "second satellite of Jupiter". In 1892, the discovery of Amalthea, whose orbit lay closer to Jupiter than those of the Galilean moons, pushed Europa to the third position. The "Voyager" probes discovered three more inner satellites in 1979, so Europa is now counted as Jupiter's sixth satellite, though it is still referred to as. The adjectival form has stabilized as "Europan".

Orbit and rotation.

Europa orbits Jupiter in just over three and a half days, with an orbital radius of about 670,900 km. With an orbital eccentricity of only 0.009, the orbit itself is nearly circular, and the orbital inclination relative to Jupiter's equatorial plane is small, at 0.470°. Like its fellow Galilean satellites, Europa is tidally locked to Jupiter, with one hemisphere of Europa constantly facing Jupiter. Because of this, there is a sub-Jovian point on Europa's surface, from which Jupiter would appear to hang directly overhead. Europa's prime meridian is a line passing through this point. Research suggests that the tidal locking may not be full, as a non-synchronous rotation has been proposed: Europa spins faster than it orbits, or at least did so in the past. This suggests an asymmetry in internal mass distribution and that a layer of subsurface liquid separates the icy crust from the rocky interior.  The slight eccentricity of Europa's orbit, maintained by the gravitational disturbances from the other Galileans, causes Europa's sub-Jovian point to oscillate around a mean position. As Europa comes slightly nearer to Jupiter, Jupiter's gravitational attraction increases, causing Europa to elongate towards and away from it. As Europa moves slightly away from Jupiter, Jupiter's gravitational force decreases, causing Europa to relax back into a more spherical shape, and creating tides in its ocean. The orbital eccentricity of Europa is continuously pumped by its mean-motion resonance with Io. Thus, the tidal flexing kneads Europa's interior and gives it a source of heat, possibly allowing its ocean to stay liquid while driving subsurface geological processes. The ultimate source of this energy is Jupiter's rotation, which is tapped by Io through the tides it raises on Jupiter and is transferred to Europa and Ganymede by the orbital resonance.  Analysis of the unique cracks lining Europa yielded evidence that it likely spun around a tilted axis at some point in time. If correct, this would explain many of Europa's features. Europa's immense network of crisscrossing cracks serves as a record of the stresses caused by massive tides in its global ocean. Europa's tilt could influence calculations of how much of its history is recorded in its frozen shell, how much heat is generated by tides in its ocean, and even how long the ocean has been liquid. Its ice layer must stretch to accommodate these changes. When there is too much stress, it cracks. A tilt in Europa's axis could suggest that its cracks may be much more recent than previously thought. The reason for this is that the direction of the spin pole may change by as much as a few degrees per day, completing one precession period over several months. A tilt could also affect the estimates of the age of Europa's ocean. Tidal forces are thought to generate the heat that keeps Europa's ocean liquid, and a tilt in the spin axis would cause more heat to be generated by tidal forces. Such additional heat would have allowed the ocean to remain liquid for a longer time. However, it has not yet been determined when this hypothesized shift in the spin axis might have occurred.

Physical characteristics.

Europa is slightly smaller than the Moon. At just over in diameter, it is the sixth-largest moon and fifteenth-largest object in the Solar System. Though by a wide margin the least massive of the Galilean satellites, it is nonetheless more massive than all known moons in the Solar System smaller than itself combined. Its bulk density suggests that it is similar in composition to the terrestrial planets, being primarily composed of silicate rock.

Internal structure.

It is estimated that Europa has an outer layer of water around thick; a part frozen as its crust, and a part as a liquid ocean underneath the ice. Recent magnetic-field data from the "Galileo" orbiter showed that Europa has an induced magnetic field through interaction with Jupiter's, which suggests the presence of a subsurface conductive layer. This layer is likely a salty liquid-water ocean. Portions of the crust are estimated to have undergone a rotation of nearly 80°, nearly flipping over (see true polar wander), which would be unlikely if the ice were solidly attached to the mantle. Europa probably contains a metallic iron core.

Surface features.

Europa is the smoothest known object in the Solar System, lacking large-scale features such as mountains and craters. However, according to one study, Europa's equator may be covered in icy spikes called penitentes, which may be up to 15 meters high, due to direct overhead sunlight on the equator, causing the ice to sublime, forming vertical cracks. Although the imaging available from the "Galileo" orbiter does not have the resolution needed to confirm this, radar and thermal data are consistent with this interpretation. The prominent markings crisscrossing Europa appear to be mainly albedo features that emphasize low topography. There are few craters on Europa, because its surface is tectonically too active and therefore young. Europa's icy crust has an albedo (light reflectivity) of 0.64, one of the highest of all moons. This indicates a young and active surface: based on estimates of the frequency of cometary bombardment that Europa experiences, the surface is about 20 to 180 million years old. There is currently no full scientific consensus among the sometimes contradictory explanations for the surface features of Europa.  The radiation level at the surface of Europa is equivalent to a dose of about 5400 mSv (540 rem) per day, an amount of radiation that would cause severe illness or death in human beings exposed for a single day.

Lineae.

Europa's most striking surface features are a series of dark streaks crisscrossing the entire globe, called "" (). Close examination shows that the edges of Europa's crust on either side of the cracks have moved relative to each other. The larger bands are more than across, often with dark, diffuse outer edges, regular striations, and a central band of lighter material. The most likely hypothesis is that the lineae on Europa were produced by a series of eruptions of warm ice as the Europan crust spread open to expose warmer layers beneath. The effect would have been similar to that seen in Earth's oceanic ridges. These various fractures are thought to have been caused in large part by the tidal flexing exerted by Jupiter. Because Europa is tidally locked to Jupiter, and therefore always maintains approximately the same orientation towards Jupiter, the stress patterns should form a distinctive and predictable pattern. However, only the youngest of Europa's fractures conform to the predicted pattern; other fractures appear to occur at increasingly different orientations the older they are. This could be explained if Europa's surface rotates slightly faster than its interior, an effect that is possible due to the subsurface ocean mechanically decoupling Europa's surface from its rocky mantle and the effects of Jupiter's gravity tugging on Europa's outer ice crust. Comparisons of "Voyager" and "Galileo" spacecraft photos serve to put an upper limit on this hypothetical slippage. A full revolution of the outer rigid shell relative to the interior of Europa takes at least 12,000 years. Studies of "Voyager" and "Galileo" images have revealed evidence of subduction on Europa's surface, suggesting that, just as the cracks are analogous to ocean ridges, so plates of icy crust analogous to tectonic plates on Earth are recycled into the molten interior. This evidence of both crustal spreading at bands and convergence at other sites suggests that Europa may have active plate tectonics, similar to Earth. However, the physics driving these plate tectonics are not likely to resemble those driving terrestrial plate tectonics, as the forces resisting potential Earth-like plate motions in Europa's crust are significantly stronger than the forces that could drive them.

Other geological features.

Other features present on Europa are circular and elliptical "lenticulae" (Latin for "freckles"). Many are domes, some are pits and some are smooth, dark spots. Others have a jumbled or rough texture. The dome tops look like pieces of the older plains around them, suggesting that the domes formed when the plains were pushed up from below.  One hypothesis states that these lenticulae were formed by diapirs of warm ice rising up through the colder ice of the outer crust, much like magma chambers in Earth's crust. The smooth, dark spots could be formed by meltwater released when the warm ice breaks through the surface. The rough, jumbled lenticulae (called regions of "chaos"; for example, Conamara Chaos) would then be formed from many small fragments of crust, embedded in hummocky, dark material, appearing like icebergs in a frozen sea.  An alternative hypothesis suggest that lenticulae are actually small areas of chaos and that the claimed pits, spots and domes are artefacts resulting from over-interpretation of early, low-resolution Galileo images. The implication is that the ice is too thin to support the convective diapir model of feature formation.  In November 2011, a team of researchers from the University of Texas at Austin and elsewhere presented evidence in the journal "Nature" suggesting that many "chaos terrain" features on Europa sit atop vast lakes of liquid water. These lakes would be entirely encased in Europa's icy outer shell and distinct from a liquid ocean thought to exist farther down beneath the ice shell. Full confirmation of the lakes' existence will require a space mission designed to probe the ice shell either physically or indirectly, for example, using radar.

Subsurface ocean.

Scientists' consensus is that a layer of liquid water exists beneath Europa's surface, and that heat from tidal flexing allows the subsurface ocean to remain liquid. Europa's surface temperature averages about at the equator and only at the poles, keeping Europa's icy crust as hard as granite. The first hints of a subsurface ocean came from theoretical considerations of tidal heating (a consequence of Europa's slightly eccentric orbit and orbital resonance with the other Galilean moons). "Galileo" imaging team members argue for the existence of a subsurface ocean from analysis of "Voyager" and "Galileo" images. The most dramatic example is "chaos terrain", a common feature on Europa's surface that some interpret as a region where the subsurface ocean has melted through the icy crust. This interpretation is controversial. Most geologists who have studied Europa favor what is commonly called the "thick ice" model, in which the ocean has rarely, if ever, directly interacted with the present surface. The best evidence for the thick-ice model is a study of Europa's large craters. The largest impact structures are surrounded by concentric rings and appear to be filled with relatively flat, fresh ice; based on this and on the calculated amount of heat generated by Europan tides, it is estimated that the outer crust of solid ice is approximately 10–30 km (6–19 mi) thick, including a ductile "warm ice" layer, which could mean that the liquid ocean underneath may be about deep. This leads to a volume of Europa's oceans of 3 × 10 m, between two or three times the volume of Earth's oceans.  The thin-ice model suggests that Europa's ice shell may be only a few kilometers thick. However, most planetary scientists conclude that this model considers only those topmost layers of Europa's crust that behave elastically when affected by Jupiter's tides. One example is flexure analysis, in which Europa's crust is modeled as a plane or sphere weighted and flexed by a heavy load. Models such as this suggest the outer elastic portion of the ice crust could be as thin as. If the ice shell of Europa is really only a few kilometers thick, this "thin ice" model would mean that regular contact of the liquid interior with the surface could occur through open ridges, causing the formation of areas of chaotic terrain.

Composition.

The "Galileo" orbiter found that Europa has a weak magnetic moment, which is induced by the varying part of the Jovian magnetic field. The field strength at the magnetic equator (about 120 nT) created by this magnetic moment is about one-sixth the strength of Ganymede's field and six times the value of Callisto's. The existence of the induced moment requires a layer of a highly electrically conductive material in Europa's interior. The most plausible candidate for this role is a large subsurface ocean of liquid saltwater.  Since the "Voyager" spacecraft flew past Europa in 1979, scientists have worked to understand the composition of the reddish-brown material that coats fractures and other geologically youthful features on Europa's surface. Spectrographic evidence suggests that the dark, reddish streaks and features on Europa's surface may be rich in salts such as magnesium sulfate, deposited by evaporating water that emerged from within. Sulfuric acid hydrate is another possible explanation for the contaminant observed spectroscopically. In either case, because these materials are colorless or white when pure, some other material must also be present to account for the reddish color, and sulfur compounds are suspected.  Another hypothesis for the colored regions is that they are composed of abiotic organic compounds collectively called tholins. The morphology of Europa's impact craters and ridges is suggestive of fluidized material welling up from the fractures where pyrolysis and radiolysis take place. In order to generate colored tholins on Europa there must be a source of materials (carbon, nitrogen, and water) and a source of energy to make the reactions occur. Impurities in the water ice crust of Europa are presumed both to emerge from the interior as cryovolcanic events that resurface the body, and to accumulate from space as interplanetary dust. Tholins bring important astrobiological implications, as they may play a role in prebiotic chemistry and abiogenesis.  The presence of sodium chloride in the internal ocean has been suggested by a 450 nm absorption feature, characteristic of irradiated NaCl crystals, that has been spotted in HST observations of the chaos regions, presumed to be areas of recent subsurface upwelling.

Sources of heat.

Tidal heating occurs through the tidal friction and tidal flexing processes caused by tidal acceleration: orbital and rotational energy are dissipated as heat in the core of the moon, the internal ocean, and the ice crust.

Tidal friction.

Ocean tides are converted to heat by frictional losses in the oceans and their interaction with the solid bottom and with the top ice crust. In late 2008, it was suggested Jupiter may keep Europa's oceans warm by generating large planetary tidal waves on Europa because of its small but non-zero obliquity. This generates so-called Rossby waves that travel quite slowly, at just a few kilometers per day, but can generate significant kinetic energy. For the current axial tilt estimate of 0.1 degree, the resonance from Rossby waves would contain 7.3 J of kinetic energy, which is two thousand times larger than that of the flow excited by the dominant tidal forces. Dissipation of this energy could be the principal heat source of Europa's ocean.

Tidal flexing.

Tidal flexing kneads Europa's interior and ice shell, which becomes a source of heat. Depending on the amount of tilt, the heat generated by the ocean flow could be 100 to thousands of times greater than the heat generated by the flexing of Europa's rocky core in response to gravitational pull from Jupiter and the other moons circling that planet. Europa's seafloor could be heated by the moon's constant flexing, driving hydrothermal activity similar to undersea volcanoes in Earth's oceans.  Experiments and ice modeling published in 2016, indicate that tidal flexing dissipation can generate one order of magnitude more heat in Europa's ice than scientists had previously assumed. Their results indicate that most of the heat generated by the ice actually comes from the ice's crystalline structure (lattice) as a result of deformation, and not friction between the ice grains. The greater the deformation of the ice sheet, the more heat is generated.

Radioactive decay.

In addition to tidal heating, the interior of Europa could also be heated by the decay of radioactive material (radiogenic heating) within the rocky mantle. But the models and values observed are one hundred times higher than those that could be produced by radiogenic heating alone, thus implying that tidal heating has a leading role in Europa.

Plumes.

The Hubble Space Telescope acquired an image of Europa in 2012 that was interpreted to be a plume of water vapour erupting from near its south pole. The image suggests the plume may be high, or more than 20 times the height of Mt. Everest. It has been suggested that if they exist, they are episodic and likely to appear when Europa is at its farthest point from Jupiter, in agreement with tidal force modeling predictions. Additional imaging evidence from the Hubble Space Telescope was presented in September 2016.  In May 2018, astronomers provided supporting evidence of water plume activity on Europa, based on an updated critical analysis of data obtained from the "Galileo" space probe, which orbited Jupiter between 1995 and 2003. "Galileo" flew by Europa in 1997 within of the moon's surface and the researchers suggest it may have flown through a water plume. Such plume activity could help researchers in a search for life from the subsurface European ocean without having to land on the moon.  The tidal forces are about 1,000 times stronger than the Moon's effect on Earth. The only other moon in the Solar System exhibiting water vapor plumes is Enceladus. The estimated eruption rate at Europa is about 7000 kg/s compared to about 200 kg/s for the plumes of Enceladus. If confirmed, it would open the possibility of a flyby through the plume and obtain a sample to analyze "in situ" without having to use a lander and drill through kilometres of ice.

Atmosphere.

Observations with the Goddard High Resolution Spectrograph of the Hubble Space Telescope, first described in 1995, revealed that Europa has a thin atmosphere composed mostly of molecular oxygen (O), and some water vapor. The surface pressure of Europa's atmosphere is 0.1 μPa, or 10 times that of the Earth. In 1997, the "Galileo" spacecraft confirmed the presence of a tenuous ionosphere (an upper-atmospheric layer of charged particles) around Europa created by solar radiation and energetic particles from Jupiter's magnetosphere, providing evidence of an atmosphere.  Unlike the oxygen in Earth's atmosphere, Europa's is not of biological origin. The surface-bounded atmosphere forms through radiolysis, the dissociation of molecules through radiation. Solar ultraviolet radiation and charged particles (ions and electrons) from the Jovian magnetospheric environment collide with Europa's icy surface, splitting water into oxygen and hydrogen constituents. These chemical components are then adsorbed and "sputtered" into the atmosphere. The same radiation also creates collisional ejections of these products from the surface, and the balance of these two processes forms an atmosphere. Molecular oxygen is the densest component of the atmosphere because it has a long lifetime; after returning to the surface, it does not stick (freeze) like a water or hydrogen peroxide molecule but rather desorbs from the surface and starts another ballistic arc. Molecular hydrogen never reaches the surface, as it is light enough to escape Europa's surface gravity.  Observations of the surface have revealed that some of the molecular oxygen produced by radiolysis is not ejected from the surface. Because the surface may interact with the subsurface ocean (considering the geological discussion above), this molecular oxygen may make its way to the ocean, where it could aid in biological processes. One estimate suggests that, given the turnover rate inferred from the apparent ~0.5 Gyr maximum age of Europa's surface ice, subduction of radiolytically generated oxidizing species might well lead to oceanic free oxygen concentrations that are comparable to those in terrestrial deep oceans.  The molecular hydrogen that escapes Europa's gravity, along with atomic and molecular oxygen, forms a gas torus in the vicinity of Europa's orbit around Jupiter. This "neutral cloud" has been detected by both the "Cassini" and "Galileo" spacecraft, and has a greater content (number of atoms and molecules) than the neutral cloud surrounding Jupiter's inner moon Io. Models predict that almost every atom or molecule in Europa's torus is eventually ionized, thus providing a source to Jupiter's magnetospheric plasma.

Exploration.

Exploration of Europa began with the Jupiter flybys of "Pioneer 10" and "11" in 1973 and 1974 respectively. The first closeup photos were of low resolution compared to later missions. The two Voyager probes traveled through the Jovian system in 1979, providing more-detailed images of Europa's icy surface. The images caused many scientists to speculate about the possibility of a liquid ocean underneath. Starting in 1995, the "Galileo" space probe orbited Jupiter for eight years, until 2003, and provided the most detailed examination of the Galilean moons to date. It included the "Galileo Europa Mission" and "Galileo Millennium Mission", with numerous close flybys of Europa. In 2007, "New Horizons" imaged Europa, as it flew by the Jovian system while on its way to Pluto.

Future missions.

Conjectures regarding extraterrestrial life have ensured a high profile for Europa and have led to steady lobbying for future missions. The aims of these missions have ranged from examining Europa's chemical composition to searching for extraterrestrial life in its hypothesized subsurface oceans. Robotic missions to Europa need to endure the high-radiation environment around itself and Jupiter. Europa receives about 5.40 Sv of radiation per day.  In 2011, a Europa mission was recommended by the U.S. Planetary Science Decadal Survey. In response, NASA commissioned Europa lander concept studies in 2011, along with concepts for a Europa flyby ("Europa Clipper"), and a Europa orbiter. The orbiter element option concentrates on the "ocean" science, while the multiple-flyby element ("Clipper") concentrates on the chemistry and energy science. On 13 January 2014, the House Appropriations Committee announced a new bipartisan bill that includes $80 million funding to continue the Europa mission concept studies.

Old proposals.

In the early 2000s, "Jupiter Europa Orbiter" led by NASA and the "Jupiter Ganymede Orbiter" led by the ESA were proposed together as an Outer Planet Flagship Mission to Jupiter's icy moons called Europa Jupiter System Mission, with a planned launch in 2020. In 2009 it was given priority over "Titan Saturn System Mission". At that time, there was competition from other proposals. Japan proposed "Jupiter Magnetospheric Orbiter".  "Jovian Europa Orbiter" was an ESA Cosmic Vision concept study from 2007. Another concept was "Ice Clipper", which would have used an impactor similar to the "Deep Impact" mission—it would make a controlled crash into the surface of Europa, generating a plume of debris that would then be collected by a small spacecraft flying through the plume.  "Jupiter Icy Moons Orbiter" (JIMO) was a partially developed fission-powered spacecraft with ion thrusters that was cancelled in 2006. It was part of Project Prometheus. The "Europa Lander Mission" proposed a small nuclear-powered Europa lander for JIMO. It would travel with the orbiter, which would also function as a communication relay to Earth.  "Europa Orbiter" – Its objective would be to characterize the extent of the ocean and its relation to the deeper interior. Instrument payload could include a radio subsystem, laser altimeter, magnetometer, Langmuir probe, and a mapping camera. The "Europa Orbiter" received a go-ahead in 1999 but was canceled in 2002. This orbiter featured a special ice-penetrating radar that would allow it to scan below the surface.  More ambitious ideas have been put forward including an impactor in combination with a thermal drill to search for biosignatures that might be frozen in the shallow subsurface.  Another proposal put forward in 2001 calls for a large nuclear-powered "melt probe" (cryobot) that would melt through the ice until it reached an ocean below. Once it reached the water, it would deploy an autonomous underwater vehicle (hydrobot) that would gather information and send it back to Earth. Both the cryobot and the hydrobot would have to undergo some form of extreme sterilization to prevent detection of Earth organisms instead of native life and to prevent contamination of the subsurface ocean. This suggested approach has not yet reached a formal conceptual planning stage.

Habitability potential.

So far, there is no evidence that life exists on Europa, but Europa has emerged as one of the most likely locations in the Solar System for potential habitability. Life could exist in its under-ice ocean, perhaps in an environment similar to Earth's deep-ocean hydrothermal vents. Even if Europa lacks volcanic hydrothermal activity, a 2016 NASA study found that Earth-like levels of hydrogen and oxygen could be produced through processes related to serpentinization and ice-derived oxidants, which do not directly involve volcanism. In 2015, scientists announced that salt from a subsurface ocean may likely be coating some geological features on Europa, suggesting that the ocean is interacting with the seafloor. This may be important in determining if Europa could be habitable. The likely presence of liquid water in contact with Europa's rocky mantle has spurred calls to send a probe there.  The energy provided by tidal forces drives active geological processes within Europa's interior, just as they do to a far more obvious degree on its sister moon Io. Although Europa, like the Earth, may possess an internal energy source from radioactive decay, the energy generated by tidal flexing would be several orders of magnitude greater than any radiological source. Life on Europa could exist clustered around hydrothermal vents on the ocean floor, or below the ocean floor, where endoliths are known to inhabit on Earth. Alternatively, it could exist clinging to the lower surface of Europa's ice layer, much like algae and bacteria in Earth's polar regions, or float freely in Europa's ocean. If Europa's ocean is too cold, biological processes similar to those known on Earth could not take place. If it is too salty, only extreme halophiles could survive in that environment. In 2010, a model proposed by Richard Greenberg of the University of Arizona proposed that irradiation of ice on Europa's surface could saturate its crust with oxygen and peroxide, which could then be transported by tectonic processes into the interior ocean. Such a process could render Europa's ocean as oxygenated as our own within just 12 million years, allowing the existence of complex, multicellular lifeforms.  Evidence suggests the existence of lakes of liquid water entirely encased in Europa's icy outer shell and distinct from a liquid ocean thought to exist farther down beneath the ice shell. If confirmed, the lakes could be yet another potential habitat for life. Evidence suggests that hydrogen peroxide is abundant across much of the surface of Europa. Because hydrogen peroxide decays into oxygen and water when combined with liquid water, the authors argue that it could be an important energy supply for simple life forms.  Clay-like minerals (specifically, phyllosilicates), often associated with organic matter on Earth, have been detected on the icy crust of Europa. The presence of the minerals may have been the result of a collision with an asteroid or comet. Some scientists have speculated that life on Earth could have been blasted into space by asteroid collisions and arrived on the moons of Jupiter in a process called lithopanspermia.

Europa, or Jupiter II, is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet of all the 79 known moons of Jupiter. It is also the sixth-largest moon in the Solar System. Europa was discovered in 1610 by Galileo Galilei and was named after Europa, the Phoenician mother of King Minos of Crete and lover of Zeus (the Greek equivalent of the Roman god Jupiter).

Europa (auch "Jupiter II") ist der zweitinnerste Mond des Planeten Jupiter. Sie ist mit einem Durchmesser von 3121 km der kleinste der vier großen Jupitermonde und der sechstgrößte Mond im Sonnensystem.


Description.

A pea is a most commonly green, occasionally golden yellow, or infrequently purple pod-shaped vegetable, widely grown as a cool season vegetable crop. The seeds may be planted as soon as the soil temperature reaches, with the plants growing best at temperatures of. They do not thrive in the summer heat of warmer temperate and lowland tropical climates, but do grow well in cooler, high altitude, tropical areas. Many cultivars reach maturity about 60 days after planting. Peas have both low-growing and vining cultivars. The vining cultivars grow thin tendrils from leaves that coil around any available support and can climb to be 1–2 m high. A traditional approach to supporting climbing peas is to thrust branches pruned from trees or other woody plants upright into the soil, providing a lattice for the peas to climb. Branches used in this fashion are sometimes called pea brush. Metal fences, twine, or netting supported by a frame are used for the same purpose. In dense plantings, peas give each other some measure of mutual support. Pea plants can self-pollinate.

History.

In early times, peas were grown mostly for their dry seeds. From plants growing wild in the Mediterranean basin, constant selection since the Neolithic dawn of agriculture improved their yield. In the early 3rd century BC Theophrastus mentions peas among the legumes that are sown late in the winter because of their tenderness. In the first century AD, Columella mentions them in "De re rustica", when Roman legionaries still gathered wild peas from the sandy soils of Numidia and Judea to supplement their rations.  In the Middle Ages, field peas are constantly mentioned, as they were the staple that kept famine at bay, as Charles the Good, count of Flanders, noted explicitly in 1124.  Green "garden" peas, eaten immature and fresh, were an innovative luxury of Early Modern Europe. In England, the distinction between field peas and garden peas dates from the early 17th century: John Gerard and John Parkinson both mention garden peas. Sugar peas, which the French called "mange-tout", for they were consumed pods and all, were introduced to France from the market gardens of Holland in the time of Henri IV, through the French ambassador. Green peas were introduced from Genoa to the court of Louis XIV of France in January 1660, with some staged fanfare; a hamper of them were presented before the King, and then were shelled by the Savoyan comte de Soissons, who had married a niece of Cardinal Mazarin; little dishes of peas were then presented to the King, the Queen, Cardinal Mazarin and Monsieur, the king's brother. Immediately established and grown for earliness warmed with manure and protected under glass, they were still a luxurious delicacy in 1696, when Mme de Maintenon and Mme de Sevigné each reported that they were "a fashion, a fury".  Modern split peas, with their indigestible skins rubbed off, are a development of the later 19th century.

Modern culinary use.

In modern times peas are usually boiled or steamed, which breaks down the cell walls and makes the taste sweeter and the nutrients more bioavailable. Along with broad beans and lentils, these formed an important part of the diet of most people in the Middle East, North Africa and Europe during the Middle Ages. By the 17th and 18th centuries, it had become popular to eat peas "green", that is, while they are immature and right after they are picked. New cultivars of peas were developed by the English during this time, which became known as "garden" or "English" peas. The popularity of green peas spread to North America. Thomas Jefferson grew more than 30 cultivars of peas on his estate. With the invention of canning and freezing of foods, green peas became available year-round, and not just in the spring as before. Fresh peas are often eaten boiled and flavored with butter and/or spearmint as a side dish vegetable. Salt and pepper are also commonly added to peas when served. Fresh peas are also used in pot pies, salads and casseroles. Pod peas (snow peas and snap peas) are used in stir-fried dishes, particularly those in American Chinese cuisine. Pea pods do not keep well once picked, and if not used quickly, are best preserved by drying, canning or freezing within a few hours of harvest.  In India, fresh peas are used in various dishes such as "aloo matar" (curried potatoes with peas) or "matar paneer" (paneer cheese with peas), though they can be substituted with frozen peas as well. Peas are also eaten raw, as they are sweet when fresh off the bush.Green Peas known as Hasiru Batani in Kannada are used to make curry and Gasi. Split peas are also used to make "dal", particularly in Guyana, and Trinidad, where there is a significant population of Indians.  Dried peas are often made into a soup or simply eaten on their own. In Japan, China, Taiwan and some Southeast Asian countries, including Thailand, the Philippines and Malaysia, peas are roasted and salted, and eaten as snacks. In the Philippines, peas, while still in their pods, are a common ingredient in viands and pansit. In the UK, dried yellow or green split peas are used to make pease pudding (or "pease porridge"), a traditional dish. In North America, a similarly traditional dish is split pea soup.  Pea soup is eaten in many other parts of the world, including northern Europe, parts of middle Europe, Russia, Iran, Iraq and India. In Sweden it is called "ärtsoppa", and is eaten as a traditional Swedish food which predates the Viking Age. This food was made from a fast-growing pea that would mature in a short growing season. "Ärtsoppa" was especially popular among the poor, who traditionally only had one pot and everything was cooked together for a dinner using a tripod to hold the pot over the fire.  In Chinese cuisine, the tender new growth [leaves and stem] dou miao (; "dòu miáo") are commonly used in stir-fries. Much like picking the leaves for tea, the farmers pick the tips off of the pea plant.  In Greece, Tunisia, Turkey, Cyprus, and other parts of the Mediterranean, peas are made into a stew with lamb and potatoes.  In Hungary and Serbia, pea soup is often served with dumplings and spiced with hot paprika. In the United Kingdom, dried, rehydrated and mashed marrowfat peas, or cooked green split peas, known as mushy peas, are popular, originally in the north of England, but now ubiquitously, and especially as an accompaniment to fish and chips or meat pies, particularly in fish and chip shops. Sodium bicarbonate is sometimes added to soften the peas. In 2005, a poll of 2,000 people revealed the pea to be Britain's seventh favourite culinary vegetable.  Processed peas are mature peas which have been dried, soaked and then heat treated (processed) to prevent spoilage—in the same manner as pasteurizing. Cooked peas are sometimes sold dried and coated with wasabi, salt, or other spices.  In North America pea milk is produced and sold as an alternative to cow milk for a variety of reasons.

Manufacturing frozen peas.

In order to freeze and preserve peas, they must first be grown, picked, and shelled. Usually, the more tender the peas are, the more likely that they will be used in the final product. The peas must be put through the process of freezing shortly after being picked so that they do not spoil too soon. Once the peas have been selected, they are placed in ice water and allowed to cool. After, they are sprayed with water to remove any residual dirt or dust that may remain on them. The next step is blanching. The peas are boiled for a few minutes to remove any enzymes that may shorten their shelf life. They are then cooled and removed from the water. The final step is the actual freezing to produce the final product. This step may vary considerably; some companies freeze their peas by air blast freezing, where the vegetables are put through a tunnel at high speeds and frozen by cold air. Finally, the peas are packaged and shipped out for retail sale.

Grading.

Pea grading involves sorting peas by size, in which the smallest peas are graded as the highest quality for their tenderness. Brines may be used, in which peas are floated, from which their density can be determined.

Nutritional value.

Peas are starchy, but high in fiber, protein, vitamin A, vitamin B6, vitamin C, vitamin K, phosphorus, magnesium, copper, iron, zinc and lutein. Dry weight is about one-quarter protein and one-quarter sugar. Pea seed peptide fractions have less ability to scavenge free radicals than glutathione, but greater ability to chelate metals and inhibit linoleic acid oxidation.

Varieties.

Garden peas.

There are many varieties (cultivars) of garden peas. Some of the most common varieties are listed here. "PMR" indicates some degree of powdery mildew resistance; "afila" types, also called semi-leafless, have clusters of tendrils instead of leaves. Unless otherwise noted these are so called dwarf varieties which grow to an average height of about 1m. Giving the vines support is recommended, but not required. Extra dwarf are suitable for container growing, reaching only about 25 cm. Tall varieties grow to about 2m with support required.

Sugar peas.

Sugar peas or edible-pod peas (, "eat-all pea"), lack the tough membrane inside the pod wall and have tender edible pods. There are two main types:  The name "sugar pea" includes both types, and therefore it can be synonymous with either snow peas or snap peas in different dictionaries.  Snow peas and snap peas both belong to Macrocarpon Group, a cultivar group based on the variety "Pisum sativum" var. "macrocarpum" named in 1825. It was described as having very compressed non-leathery edible pods in the original publication.  The scientific name "Pisum sativum" var. "saccharatum" is often misused for snow peas. The variety under this name was described as having sub-leathery and compressed-terete pods and a French name of "petit pois". The description is inconsistent with the appearance of snow peas, and therefore botanists have replace this name with "Pisum sativum" var. "macrocarpum."

Field peas.

The field pea is a type of pea sometimes called "P. sativum" subsp. "arvense" (L.) Asch. It is also known as dun (grey-brown) pea, Kapucijner pea, or Austrian winter pea, and is one of the oldest domesticated crops, cultivated for at least 7,000 years. Field peas are now grown in many countries for both human consumption and stockfeed. There are several cultivars and colors including blue, dun (brown), maple and white. This pea should not be confused with the cowpea ("Vigna unguiculata") which is sometimes called the "field pea" in warmer climates.  It is a climbing annual legume with weak, viny, and relatively succulent stems. Vines often are 4 to 5 feet (120 to 150 cm) long, but when grown alone, field pea’s weak stems prevent it from growing more than 1.5 to 2 feet (45 to 60 cm) tall. Leaves have two leaflets and a tendril. Flowers are white, pink, or purple. Pods carry seeds that are large (4,000 seeds/lb), nearly spherical, and white, gray, green, or brown. The root system is relatively shallow and small, but well nodulated.  The field pea is a cool-season legume crop that is grown on over 25 million acres worldwide. It has been an important grain legume crop for millennia, seeds showing domesticated characteristics dating from at least 7000 years ago have been found in archaeological sites around what is now Turkey. Field peas or "dry peas" are marketed as a dry, shelled product for either human or livestock food, unlike the garden pea, which is marketed as a fresh or canned vegetable. The major producing countries of field peas are Russia and China, followed by Canada, Europe, Australia and the United States. Europe, Australia, Canada and the United States raise over 4.5 million acres and are major exporters of peas. In 2002, there were approximately 300,000 acres of field peas grown in the United States.

Pests and diseases.

A variety of diseases affect peas through a number of pathogens, including insects, viruses, bacteria and fungi. In particular, virus disease of peas has worldwide economic importance.  Additionally, insects such as the pea leaf weevil ("Sitona lineatus") can damage peas and other pod fruits. The pea leaf weevil is native to Europe, but has spread to other places such as Alberta, Canada. They are about — long and are distinguishable by three light-coloured stripes running length-wise down the thorax. The weevil larvae feed on the root nodules of pea plants, which are essential to the plants' supply of nitrogen, and thus diminish leaf and stem growth. Adult weevils feed on the leaves and create a notched, "c-shaped" appearance on the outside of the leaves.

Peas in science.

In the mid-19th century, Austrian monk Gregor Mendel's observations of pea pods led to the principles of Mendelian genetics, the foundation of modern genetics. He ended up growing and examining about 28,000 pea plants in the course of his experiments.  Mendel chose peas for his experiments because he could grow them easily, develop pure-bred strains, protect them from cross-pollination, and control their pollination. Mendel cross-bred tall and dwarf pea plants, green and yellow peas, purple and white flowers, wrinkled and smooth peas, and a few other traits. He then observed the resulting offspring. In each of these cases, one trait is dominant and all the offspring, or Filial-1 (abbreviated F) generation, showed the dominant trait. Then he crossed members of the F generation together and observed their offspring, the Filial-2 (abbreviated F) generation. The F plants had the dominant trait in approximately a 3:1 ratio.  Mendel reasoned that each parent had a 'vote' in the appearance of the offspring, and the non-dominant, or recessive, trait appeared only when it was inherited from both parents. He did further experiments that showed each trait is separately inherited. Unwittingly, Mendel had solved a major problem with Charles Darwin's theory of evolution: how new traits were preserved and not blended back into the population, a question Darwin himself did not answer. Mendel's work was published in an obscure Austrian journal and was not rediscovered until about 1900.  Recently, extracts from garden pea have shown inhibitory activity on porcine pancreatic lipase in vitro.

Genome.

The pea karyotype consists of seven chromosomes, five of which are acrocentric and two submetacentric. Despite its scientific popularity, its relatively large genome size (4.45Gb) made it challenging to sequence compared to other legumes such as "Medicago truncatula" and soybeans. The International Pea Genome Sequencing Consortium was formed to develop the first pea reference genome, and the draft assembly was officially announced in September 2019. It covers 88% of the genome (3.92Gb) and predicted 44,791 gene-coding sequences. The pea used for the assembly was the inbred French cultivar "Caméor".

Peas in medicine.

Some people experience allergic reactions to peas, as well as lentils, with vicilin or convicilin as the usual allergens.  Favism, or Fava-bean-ism, is a genetic deficiency of the enzyme glucose-6-phosphate dehydrogenase that affects Jews, other Middle Eastern Semitic peoples and other descendants of the Mediterranean coastal regions. In this condition, the toxic reaction to eating most, if not all, beans is hemolytic anemia, and in severe cases the released circulating free hemoglobin causes acute kidney injury.

Nitrogen-fixing ability.

Peas, like many legumes, contain symbiotic bacteria called "Rhizobia" within root nodules of their root systems. These bacteria have the special ability to fix nitrogen from atmospheric, molecular nitrogen (N) into ammonia (NH). The chemical reaction is: Ammonia is then converted to another form, ammonium (NH), usable by (some) plants by the following reaction: The root nodules of peas and other legumes are sources of nitrogen that they can use to make amino acids, constituents of proteins. Hence, legumes are good sources of plant protein.  When a pea plant dies in the field, for example following the harvest, all of its remaining nitrogen, incorporated into amino acids inside the remaining plant parts, is released back into the soil. In the soil, the amino acids are converted to nitrate (NO), that is available to other plants, thereby serving as fertilizer for future crops.

Etymology.

The term "pea" originates from the Latin word "pisum", which is the latinisation of the Greek πίσον ("pison"), neuter of πίσος ("pisos") "pea". It was adopted into English as the noun "pease" (plural "peasen"), as in pease pudding. However, by analogy with other plurals ending in "-s", speakers began construing "pease" as a plural and constructing the singular form by dropping the "-s", giving the term "pea". This process is known as back-formation.

The pea is most commonly the small spherical seed or the seed-pod of the pod fruit Pisum sativum. Each pod contains several peas, which can be green or yellow. Botanically, pea pods are fruit, since they contain seeds and develop from the ovary of a (pea) flower. The name is also used to describe other edible seeds from the Fabaceae such as the pigeon pea ("Cajanus cajan"), the cowpea ("Vigna unguiculata"), and the seeds from several species of "Lathyrus".

Die Erbse ("Pisum sativum"), auch Gartenerbse oder Speiseerbse genannt, ist eine Pflanzenart aus der Gattung Erbsen ("Pisum") in der Unterfamilie Schmetterlingsblütler (Faboideae) innerhalb der Familie der Hülsenfrüchtler (Fabaceae, Leguminosae). Ursprünglich aus Kleinasien stammend, ist die Erbse seit Jahrtausenden eine wichtige Nutzpflanze. Sie enthält viel Protein und wird als Gemüse und als Tierfutter verwendet.


History.

The Alaska Native Language Center believes that the common ancestral language of the Eskimo languages and of Aleut divided into the Eskimo and Aleut branches at least 4,000 years ago. The Eskimo language family split into the Yupik and Inuit branches around 1,000 years ago.  The Eskimo–Aleut languages are among the native languages of the Americas. This is a geographical category, not a genealogical one. The Eskimo–Aleut languages are not demonstrably related to the other language families of North America and are believed to represent a separate, and the last, prehistoric migration of people from Asia.  Alexander Vovin (2015) notes that Northern Tungusic languages, which are spoken in eastern Siberia and northeastern China, have Eskimo-Aleut loanwords that are not found in Southern Tungusic, implying that Eskimo-Aleut was once much more widely spoken in eastern Siberia. Vovin (2015) estimates that the Eskimo-Aleut loanwords in Northern Tungusic had been borrowed no more than 2,000 years ago, which was when Tungusic was spreading up north from its homeland in the middle reaches of the Amur River. Vovin (2015) considers the homeland ("Urheimat") of Proto-Eskimo-Aleut to be in Siberia rather than in Alaska.

Position among the world's language families.

Eskimo–Aleut does not have any genetic relationship to any of the world's other language families that is generally accepted by linguists at the present time. There is general agreement that it is not closely related to the other language families of North America. The more credible proposals on the external relations of Eskimo–Aleut all concern one or more of the language families of northern Eurasia, such as Chukotko-Kamchatkan just across the Bering Strait. One of the first such proposals, the Eskimo–Uralic hypothesis, was suggested by the pioneering Danish linguist Rasmus Rask in 1818, upon noticing similarities between Greenlandic and Finnish. Perhaps the most fully developed such proposal to date is Michael Fortescue's Uralo-Siberian hypothesis, published in 1998.  More recently Joseph Greenberg (2000–2002) suggested grouping Eskimo–Aleut with all of the language families of northern Eurasia (Indo-European, Uralic, Altaic, Korean, Japanese, Ainu, Nivkh/Gilayak, and Chukchi-Kamchatkan), with the exception of Yeniseian, in a proposed language family called Eurasiatic. Such proposals are not generally accepted. Criticisms have been made stating that Greenberg's hypothesis is ahistorical, meaning that it lacks and sacrifices known historical elements of language in favour of external similarities. Although the Eurasiatic hypothesis is generally disregarded by linguists, one critique by Stefan Georg and Alexander Vovin stated that they were not willing to disregard the theory immediately although ultimately agreed that Greenberg's conclusion was dubious. Greenberg explicitly states that his developments were based on the previous macro-comparative work done by Vladislav Illich-Svitych and Bomhard and Kerns. By providing evidence of lexical comparison, Greenberg hoped that it would strengthen his hypothesis.  Despite all these efforts, the Eurasiatic language theory was overruled on the basis that mass comparison is not accurate enough an approach. In comparative linguistics, the comparative method bases its validity on highly regular changes, not occasional semantic and phonological similarities, which is what the Eurasiatic hypothesis provides.  In the 1960s Morris Swadesh suggested a connection with the Wakashan languages. This was picked up and expanded by Jan Henrik Holst (2005).

Notable features.

Every word must have only one root (free morpheme) always at the beginning. Eskimo–Aleut languages have a relatively small number of roots: in the case of Central Alaskan Yup'ik, around two thousand. Following the root are a number of "postbases", which are bound morphemes that add to the basic meaning of the root. If the meaning of the postbase is to be expressed alone, a special neutral root (in the case of Central Alaskan Yup'ik and Inuktitut "pi") is used.  The basic word schema is as follows: root-(affixes)-inflection-(enclitic). Below is an example from Central Siberian Yupik.  There are a total of three affixes internal to the word 'angyagh.' The root (or free morpheme) 'angyagh' and the inflection '-tuq' on the right consist of the indicative mood marker plus third person singular. The enclitic –lu ‘also’ follows the inflection.  Following the postbases are non-lexical suffixes that indicate case on nouns and person and mood on verbs. The number of cases varies, with Aleut languages having a greatly reduced case system compared to Eskimo. The Eskimo languages are ergative–absolutive in nouns and in Yup'ik languages, also in verbal person marking. All Eskimo–Aleut languages have obligatory verbal agreement with agent and patient in transitive clauses, and there are special suffixes used for this purpose in subordinate clauses, which makes these languages, like most in the North Pacific, highly "complement deranking".  At the end of a word there can be one of a small number of clitics with meanings such as "but" or indicating a polar question.  Phonologically, the Eskimo–Aleut languages resemble other language families of northern North America (Na-Dene and Tsimshianic) and far-eastern Siberia (Chukotko-Kamchatkan). There are usually only three vowels—,, —though some Yup'ik dialects also have. All Eskimo–Aleut languages lack ejectives, in which they resemble the Siberian languages more than the North American ones. Eskimo–Aleut languages possess voiceless plosives at four positions (bilabial, coronal, velar and uvular) in all languages except Aleut, which has lost the bilabial stops (though it has retained the nasal). There are contrasting voiced and voiceless fricatives at the same positions, and in the Eskimo subfamily a voiceless alveolar lateral fricative is also present. A rare feature of many dialects of Yup'ik and Aleut is contrasting voiceless nasals.

Phonology.

Eskimo.

The following vowels and consonants were taken from Michael Fortescue et al., 2010

Vowels.

Eskimo /ə/ corresponds to Aleut /i/.

Consonants.

Inuit allows only a single initial consonant and no more than two successive consonants between vowels.  Yupik lacks the consonant assimilation process so common to Inuit.  Consonants in parentheses are non-Proto-Eskimo phonemes.

Aleut.

The following vowels and consonants were taken from Knut Bergsland, (1997).

Vowels.

The Aleut language has six vowels in total: three short vowels /i/, /u/, /a/, and three long vowels /iː/, /uː/, /aː/. Orthographically, they would be spelled "ii", "uu", and "aa". There are no diphthongs in Aleut vowels. The length of the vowel is dependent upon three characteristics: stress, surrounding consonants, and in particularly Eastern Aleut, surrounding vowels. Short vowels are in initial position if a following consonant is velar or labial. For example: the demonstratives "uka", "ika", and "aka".  Long vowels are lower than their short counterpart vowels, but are less retracted if they make contact with a uvular consonant. For example: "uuquchiing" 'blue fox,' "qiiqix̂"'storm-petrel', and "qaaqaan" 'eat it!'

Consonants.

The Aleut consonants featured below include single Roman letters, digraphs, and one trigraph. Phonemes in parenthesis are found only in Russian and English loanwords, the phoneme in italics is found only in Eastern Aleut, and the bold phonemes are a part of the standard Aleut inventory.  Aleut lacks labial stops and allows clusters of up to three consonants as well as consonant clusters in word initial position.  Noteworthy phonological features: lack of a [p] and its voiceless nasals

Morphology.

Language type.

Polysynthetic language.

Eskimo-Aleut is polysynthetic, which features a process in which a single word is able to contain multiple post-bases or morphemes. The Eskimo–Aleut languages are exclusively suffixing (with the exception of one prefix in Inuktitut that appears in demonstratives). Suffixes are able to combine and ultimately create an unlimited number of words. Some of the morphemes that are able to attach contain features such as carrying nominal subjects and objects, adverbial information, direct objects, and spatial noun phrases. Polysynthetic languages are said to be a form of extreme agglutination, which allows single words to carry the same information that another language expresses in whole clauses. For example, in central Alaskan Yupik, one can say: As a polysynthetic language, Eskimo-Aleut is concerned with what "each morpheme means, which categories it can attach to, whether there is any category change, etc. and what type of morphophonological effect occurs to the left as it attaches to the stem".

Morphosyntactic alignment.

"Ergative-absolutive language:"  Eskimo-Aleut follows the basic word order of Subject-Object-Verb (SOV).  Eskimo is an ergative–absolutive language. This means subjects of intransitive verbs and objects of transitive verbs are marked with the absolutive case, while subjects of transitive verbs are marked with the ergative case.  Aleut is not an ergative-absolutive language. It doesn't matter if the verb is transitive or intransitive—subjects and objects are not marked differently.  If a transitive object or an object of possession is openly communicated, ergative case marking will not be expressed. If a transitive object or object of possession is not openly communicated, then ergative case marking will be expressed.  Example of case marking in Aleut:

Syntax.

The syntax of Eskimo-Aleut is concerned with the functional use of its morphological structure. The two language branches, although part of the same family, have separated and detached themselves in relation to grammatical similarities. Bergsland states that Aleut, which was once a language more similar to Proto-Eskimo than the current Eskimo languages themselves, has distanced itself from the ancient language.  The case inflections, "relative *-m, instrumental *-mEk/meN, and locative *-mi have undergone phonological merger and led to a completely different explanation of ergative morphology in Proto-Eskimo.  In order to further explain the profound changes that have occurred in Aleutian syntax, Bergsland proposed the Domino Effect, which is ultimately the chronological order of Aleut’s unique features. Below is a step by step list of the 'domino effect':  "The Domino Effect:"

Vocabulary comparison.

The following is a comparison of cognates among the basic vocabulary across the Eskimo–Aleut language family (about 122 words). Note that empty cells do not imply that a particular language is lacking a word to describe the concept, but rather that the word for the concept in that language is formed from another stem and is not a cognate with the other words in the row. Also, there may be shifts in the meaning from one language to another, and so the "common meaning" given is only approximate. In some cases the form given is found only in some dialects of the language. Forms are given in native Latin orthographies unless otherwise noted.  Cognates of the Eskimo language can be found in Michael Fortescue et al., 2010.  Cognates of the Aleut language can be found in Knut Bergsland, 1997.  There are two types of pronouns in Eskimo-Aleut: independent pronouns and pronominal pronouns.  In Eskimo-Aleut, singular, dual and plural nouns are marked by inflectional suffixes, and if they are possessed, the number marker is followed by pronominal suffixes that specify the (human) possessor. There are no genders in the Eskimo–Aleut languages, and this can be seen in the 4 persons: my, your, his/her, his/her own.  "His/Her own" specifies ownership, in contrast with "his/her", which does not. E.g., "his" house vs. "his own" house. (See Possessive determiner § Semantics.)  Aleut uses independent pronouns, instead of pronominal marking on verbs. On the other hand, Eskimo languages has 4 persons and 3 numbers marked by pronominal suffixes.

The Eskimo–Aleut languages (), Eskaleut languages, or Inuit-Yupik-Unangan languages are a language family native to Alaska, Nunavut, northern Northwest Territories (Inuvialuit Settlement Region), northern Quebec (Nunavik), northern Labrador (Nunatsiavut), Greenland and far eastern Russia (Chukotka Peninsula). It is also known as "Eskaleutian", "Eskaleutic" or "Inuit–Yupik-Unangan".

Die eskimo-aleutischen Sprachen bilden eine kleine Sprachfamilie, deren Idiome von etwa 105.000 Menschen in Nordostsibirien, Alaska, Nordkanada und Grönland gesprochen werden. Zu den Eskimosprachen gehören das Inuktitut oder auch Eastern Eskimo, das im Norden Alaskas, in Kanada und Grönland verbreitet ist, sowie die Yupiksprachen im Westen Alaskas und in Sibirien. Der aleutische Zweig besteht aus der Einzelsprache Aleutisch. Das Eskimo und die Yupiksprachen bilden jeweils ein Dialektkontinuum.


Geography.

The Gobi measures over from southwest to northeast and from north to south. The desert is widest in the west, along the line joining the Lake Bosten and the Lop Nor (87°–89° east). It occupies an arc of land in area as of 2007; it is the sixth-largest desert in the world and Asia's 2nd largest. Much of the Gobi is not sandy but has exposed bare rock.  In its broadest definition, the Gobi includes the long stretch of desert extending from the foot of the Pamirs (77° east) to the Greater Khingan Mountains, 116°-118° east, on the border of Manchuria; and from the foothills of the Altay, Sayan, and Yablonoi mountain ranges on the north to the Kunlun, Altyn-Tagh, and Qilian mountain ranges, which form the northern edges of the Tibetan Plateau, on the south.  A relatively large area on the east side of the Greater Khingan range, between the upper waters of the Songhua (Sungari) and the upper waters of the Liao-ho, is reckoned to belong to the Gobi by conventional usage. Some geographers and ecologists prefer to regard the western area of the Gobi region (as defined above): the basin of the Tarim in Xinjiang and the desert basin of Lop Nor and Hami (Kumul), as forming a separate and independent desert, called the Taklamakan Desert.  Archeologists and paleontologists have done excavations in the Nemegt Basin in the northwestern part of the Gobi Desert (in Mongolia), which is noted for its fossil treasures, including early mammals, dinosaur eggs, and prehistoric stone implements, some 100,000 years old.

Climate.

The Gobi is overall a cold desert, with frost and occasionally snow occurring on its dunes. Besides being quite far north, it is also located on a plateau roughly above sea level, which contributes to its low temperatures. An average of approximately of rain falls annually in the Gobi. Additional moisture reaches parts of the Gobi in winter as snow is blown by the wind from the Siberian Steppes. These winds may cause the Gobi to reach in winter to in summer.  However, the climate of the Gobi is one of great extremes, combined with rapid changes of temperature of as much as. These can occur not only seasonally but within 24 hours.  In southern Mongolia, the temperature has been recorded as low as. In contrast, in Alxa, Inner Mongolia, it rises as high as in July.  Average winter minimums are a frigid, while summertime maximums are a warm. Most of the precipitation falls during the summer.  Although the southeast monsoons reach the southeast parts of the Gobi, the area throughout this region is generally characterized by extreme dryness, especially during the winter, when the Siberian anticyclone is at its strongest. The southern and central parts of the Gobi Desert have variable plant growth due to this monsoon activity. The more northern areas of the Gobi are very cold and dry, making it unable to support much plant growth; this cold and dry weather is attributed to Siberian-Mongolian high pressure cells. Hence, the icy sandstorms and snowstorms of spring and early summer plus early January (winter).

Conservation, ecology, and economy.

The Gobi Desert is the source of many important fossils finds, including the first dinosaur eggs, twenty-six of which, averaging 9 inches in length, were uncovered in 1923.  Despite the harsh conditions, these deserts and the surrounding regions sustain many animals, including black-tailed gazelles, marbled polecats, wild Bactrian camels, Mongolian wild ass and sandplovers. They are occasionally visited by snow leopards, Gobi bears, and wolves. Lizards are especially well-adapted to the climate of the Gobi Desert, with approximately 30 species distributed across its southern Mongolian border. The most common vegetation in the Gobi desert are shrubs adapted to drought. These shrubs included gray sparrow's saltwort ("Salsola passerina"), gray sagebrush, and low grasses such as needle grass and bridlegrass. Due to livestock grazing, the amount of shrubs in the desert has decreased. Several large nature reserves have been established in the Gobi, including Gobi Gurvansaikhan National Park, Great Gobi A and Great Gobi B Strictly Protected Area.  The area is vulnerable to trampling by livestock and off-road vehicles (effects from human intervention are greater in the eastern Gobi Desert, where rainfall is heavier and may sustain livestock). In Mongolia, grasslands have been degraded by goats, which are raised by nomadic herders as source of cashmere wool.  Large copper deposits are being mined by Rio Tinto Group. The mine was and remains controversial. There was significant opposition in Mongolia's parliament to the terms under which the mine will proceed, and some are calling for the terms to be renegotiated. Specifically, the contention revolves primarily around the question of whether negotiations were fair (Rio Tinto is far better resourced) and whether Rio Tinto will pay adequate taxes on the revenues it derives from the mine (an agreement was reached whereby the operation will be exempt from windfall tax).

Desertification.

The Gobi Desert is expanding at an alarming rate through desertification, most rapidly on the southern edge into China, which is seeing of grassland overtaken every year. Dust storms have increased in frequency in the past 20 years, causing further damage to China's agriculture economy.  The northern and eastern boundaries between desert and grassland are constantly changing. This is mostly due to the climate conditions before the growing season, which influence the rate of evapotranspiration and subsequent plant growth.  The expansion of the Gobi is attributed mostly to human activities. It is part of the broader consequences of anthropogenic climate change, but locally driven by deforestation, overgrazing, and depletion of water resources. China has tried various plans to slow the expansion of the desert, which have met with some small degree of success, but no major effects. The Three-North Shelter Forest Program (or "Green Great Wall") was a Chinese government tree-planting project begun in 1978 and set to continue through 2050. The goal of the program is to reverse desertification by planting aspen and other fast-growing trees on some 36.5 million hectares across some 551 counties in 12 provinces of northern China. From 1978 to about 2004, the survival rate for trees planted as part of the Three Norths Shelter Forest System Project was low (about 15%).

Ecoregions.

The Gobi, broadly defined, can be divided into five distinct dry ecoregions, based on variations in climate and topography:

Eastern Gobi desert steppe.

The surface is extremely diversified, although there are no great differences in vertical elevation. Between Ulaanbaatar () and the small lake of Iren-dubasu-nor (), the surface is greatly eroded. Broad flat depressions and basins are separated by groups of flat-topped mountains of relatively low elevation ), through which archaic rocks crop out as crags and isolated rugged masses. The floors of the depressions lie mostly between above sea-level. Further south, between Iren-dutiasu-nor and the Yellow River, comes a region of broad tablelands alternating with flat plains, the latter ranging at altitudes of 1000–1100 m and the former at. The slopes of the plateaus are more or less steep and are sometimes penetrated by "bays" of the lowlands.  As the border-range of the Hyangan is approached, the country steadily rises up to and then to. Here small lakes frequently fill the depressions, though the water in them is generally salt or brackish. Both here and for south of Ulaanbaatar, streams are frequent and grass grows more or less abundantly. Through all the central parts, until the bordering mountains are reached, trees and shrubs are utterly absent. Clay and sand are the predominant formations; the watercourses, especially in the north, being frequently excavated deep. In many places in the flat, dry valleys or depressions farther south, beds of loess, thick, are exposed. West of the route from Ulaanbaatar to Kalgan, the country presents approximately the same general features, except that the mountains are not so irregularly scattered in groups but have more strongly defined strikes, mostly east to west, west-north-west to east-south-east, and west-south-west to east-north-east.  The altitudes are higher, those of the lowlands ranging from, and those of the ranges from higher, though in a few cases they reach altitudes of. The elevations do not form continuous chains, but make up a congeries of short ridges and groups rising from a common base and intersected by a labyrinth of ravines, gullies, glens, and basins. But the tablelands, built up of the horizontal red deposits of the Han-gai (Obruchev's Gobi formation) which are characteristic of the southern parts of eastern Mongolia, are absent here or occur only in one locality, near the Shara-muren river. They are greatly intersected by gullies or dry watercourses. Water is scarce, with no streams, no lakes, no wells, and precipitation falls seldom. The prevailing winds blow from the west and northwest, and the pall of dust overhangs the country as in the Takla Makan and the desert of Lop. Characteristic of the flora are wild garlic, "Kalidium gracile", wormwood, saxaul, "Nitraria schoberi", "Caragana", Ephedra, saltwort and the grass "Lasiagrostis splendens". The taana wild onion "Allium polyrrhizum" is the main browse eaten by many herd animals, and Mongolians claim that this is essential to produce the correct, slightly hazelnut-like flavour of camel airag (fermented milk).  This great desert country of Gobi is crossed by several trade routes, some of which have been in use for thousands of years. Among the most important are those from Kalgan (at the Great Wall) to Ulaanbaatar (); from Jiuquan (in Gansu) to Hami ; from Hami to Beijing (); from Hohhot to Hami and Barkul; and from Lanzhou (in Gansu) to Hami.

Alashan Plateau semi-desert.

The southwestern portion of the Gobi, known also as the Xitao and the Little Gobi, fills the space between the great north loop of the Yellow River on the east, the Ejin River on the west, and the Qilian Mountains and narrow rocky chain of Longshou, in altitude, on the southwest. The Ordos Desert, which covers the northeastern portion of the Ordos Plateau, in the great north loop of the Yellow River, is part of this ecoregion. It belongs to the middle basin of the three great depressions into which Potanin divides the Gobi as a whole.  "Topographically," says Nikolai Przhevalsky, "it is a perfectly level plain, which in all probability once formed the bed of a huge lake or inland sea." He concludes this based on the level area of the region as a whole, the hard saldgine clay and the sand-strewn surface and, lastly, the salt lakes which occupy its lowest parts. For hundreds of kilometers, nothing can be seen but bare sands; in some places, they continue so far without a break that the Mongols call them "Tengger" (i.e. sky). These vast expanses are absolutely waterless, nor do any oases relieve the unbroken stretches of yellow sand, which alternate with equally vast areas of saline clay or, nearer the foot of the mountains, with barren shingle. Although on the whole a level country with a general altitude of, this section, like most other parts of the Gobi, is crowned by a chequered network of hills and broken ranges going up 300 m higher. The vegetation is confined to a few varieties of bushes and a dozen kinds of grasses and herbs, the most conspicuous being saxaul ("Haloxylon ammondendron") and "Agriophyllum gobicum". The others include prickly convolvulus, field wormwood ("Artemisia campestris"), acacia, "Inula ammophila", "Sophora flavescens", "Convolvulus ammanii", "Peganum" and "Astragalus" species, but all dwarfed, deformed and starved. The fauna consists of little but antelope, wolf, fox, hare, hedgehog, marten, numerous lizards and a few birds, e.g. the sandgrouse, lark, stonechat, sparrow, crane, Henderson's ground jay ("Podoces hendersoni"), horned lark ("Eremophila alpestris"), and crested lark ("Galerida cristata").

Dzungarian Basin semi-desert.

The Yulduz valley or valley of the Haidag-gol (–) is a mini desert enclosed by two prominent members of the Shanashen Trahen Osh mountain range, namely the chucis and the kracenard pine rallies, running perpendicular and far from one another. As they proceed south, they transcend and transpose, sweeping back on east and west respectively, with Lake Bosten in between. These two ranges mark the northern and the southern edges respectively of a great swelling, which extends eastward for nearly twenty degrees of longitude. On its northern side, the Chol-tagh descends steeply, and its foot is fringed by a string of deep depressions, ranging from Lukchun ( below sea level) to Hami ( above sea-level). To the south of the Kuruk-tagh lie the desert of Lop Nur, the Kum-tagh desert, and the valley of the Bulunzir-gol. To this great swelling, which arches up between the two border-ranges of the Chol-tagh and Kuruk-tagh, the Mongols give the name of "Ghashuun-Gobi" or "Salt Desert". It is some across from north to south, and is traversed by a number of minor parallel ranges, ridges and chains of hills. Down its middle runs a broad stony valley, wide, at an elevation of. The Chol-tagh, which reaches an average altitude of, is absolutely sterile, and its northern foot rests upon a narrow belt of barren sand, which leads down to the depressions mentioned above.  The Kuruk-tagh is the greatly disintegrated, denuded and wasted relic of a mountain range which used to be of incomparably greater magnitude. In the west, between Lake Bosten and the Tarim, it consists of two, possibly of three, principal ranges, which, although broken in continuity, run generally parallel to one another, and embrace between them numerous minor chains of heights. These minor ranges, together with the principal ranges, divide the region into a series of long; narrow valleys, mostly parallel to one another and to the enclosing mountain chains, which descend like terraced steps, on the one side towards the depression of Lukchun and on the other towards the desert of Lop.  In many cases these latitudinal valleys are barred transversely by ridges or spurs, generally elevations en masse of the bottom of the valley. Where such elevations exist, there is generally found, on the east side of the transverse ridge, a cauldron-shaped depression, which some time or other has been the bottom of a former lake, but is now nearly a dry salt-basin. The surface configuration is in fact markedly similar to that which occurs in the inter-mount latitudinal valleys of the Kunlun Mountains. The hydrography of the Ghashiun-Gobi and the Kuruk-tagh is determined by these chequered arrangements of the latitudinal valleys. Most of the principal streams, instead of flowing straight down these valleys, cross them diagonally and only turn west after they have cut their way through one or more of the transverse barrier ranges.  To the highest range on the great swelling Grigory Grum-Grshimailo gives the name of Tuge-tau, its altitude being above the level of the sea and some above the crown of the swelling itself. This range he considers to belong to the Choltagh system, whereas Sven Hedin would assign it to the Kuruk-tagh. This last, which is pretty certainly identical with the range of Kharateken-ula (also known as the Kyzyl-sanghir, Sinir, and Singher Mountains), that overlooks the southern shore of the Lake Bosten, though parted from it by the drift-sand desert of Ak-bel-kum (White Pass Sands), has at first a west-northwest to east-southeast strike, but it gradually curves round like a scimitar towards the east-northeast and at the same time gradually decreases in elevation.  In 91° east, while the principal range of the Kuruk-tagh system wheels to the east-northeast, four of its subsidiary ranges terminate, or rather die away somewhat suddenly, on the brink of a long narrow depression (in which Sven Hedin sees a northeast bay of the former great Central Asian lake of Lop-nor), having over against them the écheloned terminals of similar subordinate ranges of the Pe-shan (Boy-san) system (see below). The Kuruk-tagh is throughout a relatively low, but almost completely barren range, being entirely destitute of animal life, save for hares, antelopes and wild camels, which frequent its few small, widely scattered oases. The vegetation, which is confined to these same relatively favoured spots, is of the scantiest and is mainly confined to bushes of saxaul "(Haloxylon)", "anabasis", reeds (kamish), tamarisks, poplars, and Ephedra.

European exploration.

The Gobi had a long history of human habitation, mostly by nomadic peoples. By the early 20th century, the region was under the nominal control of Manchu-China, and inhabited mostly by Mongols, Uyghurs, and Kazakhs. The Gobi Desert as a whole was known only very imperfectly to outsiders, and information was confined to observations by individual travellers from their respective itineraries across the desert. Among the European explorers who contributed to the understanding of the Gobi, the most important were the following:

The Gobi Desert () is a large desert or brushland region in East Asia. It covers parts of Northern and Northeastern China and of Southern Mongolia. The desert basins of the Gobi are bounded by the Altai Mountains and the grasslands and steppes of Mongolia on the north, by the Taklamakan Desert to the west, by the Hexi Corridor and Tibetan Plateau to the southwest and by the North China Plain to the southeast. The Gobi is notable in history as the location of several important cities along the Silk Road.

Die Wüste Gobi, oder kurz die Gobi (, ), ist ein weiträumiges Trockengebiet in Zentralasien, in der Mongolei und China. Sie besteht aus zusammenhängenden, vielgestaltigen Wüsten- und Halbwüstenlandschaften. Charakteristisch sind insbesondere die extrem wasserarmen, meist steinigen und seltener sandigen Wüsten in China, sowie die lebensfreundlicheren, weiten Steppen in der Mongolei. Mit 2,3 Millionen km2 ist sie eine der größten nichtpolaren Wüstenregionen der Erde.


Early life and career.

Roddenberry was born on August 19, 1921, in his parents' rented home in El Paso, Texas, the first child of Eugene Edward Roddenberry and Caroline "Glen" (née Golemon) Roddenberry. The family moved to Los Angeles in 1923 after Gene's father passed the Civil Service test and was given a police commission there. During his childhood, Roddenberry was interested in reading, especially pulp magazines, and was a fan of stories such as "John Carter of Mars", "Tarzan", and the "Skylark" series by E. E. Smith.  Roddenberry majored in police science at Los Angeles City College, where he began dating Eileen-Anita Rexroat and became interested in aeronautical engineering. He obtained a pilot's license through the United States Army Air Corps-sponsored Civilian Pilot Training Program. He enlisted with the USAAC on December 18, 1941, and married Eileen on June 13, 1942. He graduated from the USAAC on August 5, 1942, when he was commissioned as a second lieutenant.  He was posted to Bellows Field, Oahu, to join the 394th Bomb Squadron, 5th Bombardment Group, of the Thirteenth Air Force, which flew the Boeing B-17 Flying Fortress.  On August 2, 1943, while flying B-17E-BO, "41-2463", "Yankee Doodle", out of Espiritu Santo, the plane Roddenberry was piloting overshot the runway by and crashed into trees, crushing the nose, and starting a fire, killing two men: bombardier Sgt. John P.

Career as full-time writer and producer.

Early career.

Roddenberry was promoted to head writer for "The West Point Story", and wrote 10 scripts for the first season, about a third of the total episodes. While working for Ziv, in 1956, he pitched a series to CBS set aboard a cruise ship, "Hawaii Passage", but they did not buy it, as he wanted to become a producer and have full creative control. He wrote another script for Ziv's series "Harbourmaster" titled "Coastal Security", and signed a contract with the company to develop a show called "Junior Executive" with Quinn Martin. Nothing came of the series.  He wrote scripts for a number of other series in his early years as a professional writer, including "Bat Masterson" and "Jefferson Drum". Roddenberry's episode of the series "Have Gun – Will Travel", "Helen

"Star Trek".

When Roddenberry pitched "Star Trek" to MGM, it was warmly received, but no offer was made. He then went to Desilu Productions, but rather than being offered a one-script deal, he was hired as a producer and allowed to work on his own projects. His first was a half-hour pilot called "Police Story" (not to be confused with the anthology series created by Joseph Wambaugh), which was not picked up by the networks. Having not sold a pilot in five years, Desilu was having financial difficulties; its only success was "I Love Lucy". Roddenberry took the "Star Trek" idea to Oscar Katz, head of programming, and the duo immediately started work on a plan to sell the series to the networks. They took it to CBS, which ultimately passed on it. The duo later learned that CBS had been eager to find out about "Star Trek" because it had a science fiction series in development—"Lost in Space". Roddenberry and Katz next took the idea to Mort Werner at NBC, this time downplaying the science fiction elements and highlighting the links to "Gunsmoke" and "Wagon Train." The network funded three story ideas, and selected "The Menagerie", which was later known as "", to be made into a pilot. (The other two later became episodes of the series.) While most of the money for the pilot came from NBC, the remaining costs were covered

1970s projects.

Following the cancellation of "Star Trek," Roddenberry felt typecast as a producer of science fiction, despite his background in Westerns and police stories. He later described the period, saying, "My dreams were going downhill because I could not get work after the original series was cancelled." He felt that he was "perceived as the guy who made the show that was an expensive flop." Roddenberry had sold his interest in "Star Trek" to Paramount Studios in return for a third of the ongoing profits. However, this did not result in any quick financial gain; the studio was still claiming that the series was $500,000 in the red in 1982. He wrote and produced "Pretty Maids All in a Row" (1971), a sexploitation film directed

"Star Trek" revival.

Lacking funds in the early 1970s, Roddenberry was unable to buy the full rights to "Star Trek" for $150,000 from Paramount. Lou Scheimer approached Paramount in 1973 about creating an animated "Star Trek" series. Credited as "executive consultant" and paid $2,500 per episode, Roddenberry was granted full creative control of "". Although he read all the scripts and "sometimes [added] touches of his own", he relinquished most of his authority to "de facto" showrunner/associate producer D. C. Fontana.  Roddenberry had some difficulties with the cast. To save money, he sought not to hire George Takei and Nichelle Nichols. He neglected to inform Leonard Nimoy of this and instead, in an effort to get him to sign on, told him that he was the only member of the main cast not returning. After Nimoy discovered the deception, he demanded that Takei and Nichols play Sulu and Uhura when their characters appeared on screen; Roddenberry acquiesced. He had been promised five full seasons of the new show, but ultimately, only one and a half were produced.  However, the groundswell of vociferous fan support (6,000 attended the second New York "Star Trek" convention in

Personal life.

While at Los Angeles City College, Roddenberry began dating Eileen-Anita Rexroat. They became engaged before Roddenberry left Los Angeles during his military service, and married in June 1942 at the chapel at Kelly Field. They had two children together, Darleen Anita, and Dawn Allison. During his time in the LAPD, Roddenberry was known to have had affairs with secretarial staff. Before his work on "Star Trek", he began relationships with both Nichelle Nichols and Majel Barrett. Nichols only wrote about their relationship in her autobiography "Beyond Uhura" after Roddenberry's death. At the time, Roddenberry wanted to remain in an open relationship with both women, but Nichols, recognising Barrett's devotion to him, ended the affair as she did not want to be "the other woman to the other woman".  Barrett and he had an apartment together by the opening weeks of "Star Trek". He had planned to divorce Eileen after the first season of the show, but when it was renewed, he delayed doing so, fearing that he would not have enough time to deal with both the divorce and "Star Trek". He moved out of the family home on August 9, 1968, two weeks after the marriage of his daughter Darleen. In 1969, while scouting locations in Japan for MGM for "Pretty Maids all in a Row", he proposed to Barrett by telephone. They were married in a Shinto ceremony, as Roddenberry had considered it "sacrilegious" to use an American minister in Japan. Roddenberry and Barrett had a son together, Eugene Jr., commonly and professionally known as Rod Roddenberry, in February 1974. From 1975 until his death, Roddenberry maintained an extramarital relationship with his executive assistant, Susan Sackett.

Religious views.

Roddenberry was raised a Southern Baptist; however, as an adult, he rejected religion, and considered himself a humanist. He began questioning religion around the age of 14, and came to the conclusion that it was "nonsense". As a child, he served in the choir at his local church, but often substituted lyrics as he sang hymns. Early in his writing career, he received an award from the American Baptist Convention for "skillfully writing Christian truth and the application of Christian principles into commercial, dramatic TV scripts".

Health, decline and death.

In the late 1980s, Roddenberry was likely afflicted by the first manifestations of cerebral vascular disease and encephalopathy as a result of his longstanding recreational use of legal and illicit drugs, including alcohol, methaqualone, methylphenidate, Dexamyl, and cocaine (which he had used regularly since the production of "Star Trek: The Motion Picture"). Throughout much of his career, he had routinely used stimulants to work through the night on scripts, especially amphetamines. The effects of these substances were compounded by deleterious interactions with diabetes, high blood pressure, and antidepressant prescriptions.  Following a stroke at a family reunion in Tallahassee, Florida, in September 1989, Roddenberry's health declined further, ultimately requiring him to use a wheelchair. His right arm was paralyzed after another stroke in early October 1991, causing him ongoing pain as the muscles began to atrophy. It also caused problems with the sight in his right eye and he found communicating in full sentences difficult. At 2:00 pm, on October 24, he attended an appointment with his doctor, Dr. Ronald Rich. He arrived in the building with his staff, and began to travel up to the ninth floor in the elevator. As they reached the fifth floor, he began struggling for breath, and was wheeled into the doctor's office, where he was reclined and a nurse administered oxygen. Barrett was sent for. Upon her arrival, she held Roddenberry while encouraging him to breathe. He had a cardiopulmonary arrest, and he died in the doctor's office shortly afterwards. Cardiopulmonary resuscitation was attempted with no effect, and paramedics arrived to take him across the road to the Santa Monica Medical Center, where he was pronounced dead.  The funeral was arranged for November 1, with the public invited to the memorial service at the Hall of Liberty, within the Forest Lawn Memorial Park, in Hollywood Hills. It was a secular service; Roddenberry had been cremated before the event. More than 300 "Star Trek" fans attended, and stood in the balcony section of the hall, while the invited guests were on the floor level. Nichelle Nichols sang twice during the ceremony, first "Yesterday" and then a song she wrote herself titled "Gene". Both songs had been requested by Barrett. Several people spoke at the memorial, including Ray Bradbury, Whoopi Goldberg, Christopher Knopf, E. Jack Neuman, and Patrick Stewart. The ceremony was closed by two kilted pipers playing "Amazing Grace" as a recorded message by Roddenberry was broadcast. A four-plane flypast, in the missing man formation, followed some 30 minutes later. After his death, "Star Trek: The Next Generation" aired a two-part episode of season five, called "", which featured a dedication to Roddenberry.  Roddenberry's will left the majority of his $30 million estate to Barrett, in a trust. He also left money to his children and his first wife Eileen. However, his daughter Dawn contested the will based upon the grounds that Barrett had undue influence on her father. In a hearing held in 1993, the Los Angeles Superior Court ruled that improprieties existed in the management of the trust and removed Barrett as executor. In another decision, the court found that Roddenberry had hidden assets from "Star Trek" in the Norway Corporation to keep funds away from his first wife, and ordered the payment of 50% of those assets to Eileen, as well as punitive damages. In 1996, the California Court of Appeals ruled that the original will, which stated that anyone who contested it would be disinherited, would stand. As a result, Dawn lost $500,000 from the estate, as well as a share of the trust upon Barrett's death. The appellate court also overturned the earlier decision to award Roddenberry's first wife, Eileen, 50% of his assets. The judge called that case one "that should never have been".

Legacy.

In 1985, Gene Roddenberry was the first television writer to receive a star on the Hollywood Walk of Fame. When the Sci-Fi Channel was launched, the first broadcast was a dedication to two "science fiction pioneers": Isaac Asimov and Roddenberry. The Roddenberry crater on Mars is named after him, as is the asteroid 4659 Roddenberry. Roddenberry and "Star Trek" have been cited as inspiration for other science fiction franchises, with George Lucas crediting the series for enabling "Star Wars" to be produced. J. Michael Straczynski, creator of the "Babylon 5" franchise, appreciated "Star Trek" amongst other science fiction series and "what they had to say about who we are, and where we are going."  David Alexander collaborated with Roddenberry on a biography over two decades. Titled "Star Trek Creator", it was published in 1995. Yvonne Fern's book, "Gene Roddenberry: The Last Conversation", detailed a series of conversations she had with Roddenberry over the last months of his life. In October 2002, a plaque was placed at Roddenberry's birthplace in El Paso, Texas. The Science Fiction Hall of Fame inducted Roddenberry in 2007, and the Television Academy Hall of Fame in January 2010.

Posthumous television series.

"" was already in development when Roddenberry died. Berman said that while he never discussed the ideas for the season, he was given a blessing by Roddenberry to pursue it. Berman later stated, "I don't believe the 24th century is going to be like Gene Roddenberry believed it to be, that people will be free from poverty and greed. But if you're going to write and produce for "Star Trek", you've got to buy into that." In early 1996, Majel Barret-Roddenberry uncovered scripts for a series called "Battleground Earth". The project was sent to distributors by the Creative Artists Agency, and it was picked up

Awards and nominations.

The majority of the awards and nominations received by Roddenberry throughout his career were related to "Star Trek". He was credited for "Star Trek" during the nominations for two Emmy Awards, and won two Hugo Awards. One Hugo was a special award for the series, while another was for "The Menagerie", the episode which used footage from the original unaired pilot for

Eugene Wesley Roddenberry (August 19, 1921 – October 24, 1991) was an American television screenwriter, producer and creator of the, and its first spin-off "". Born in El Paso, Texas, Roddenberry grew up in Los Angeles, where his father was a police officer. Roddenberry flew 89 combat missions in the Army Air Forces during World War II, and worked as a commercial pilot after the war. Later, he followed in his father's footsteps and joined the Los Angeles Police Department, where he also began to write scripts for television.

Eugene Wesley „Gene“ Roddenberry (* 19. August 1921 in El Paso, Texas; † 24. Oktober 1991 in Santa Monica, Kalifornien) war ein amerikanischer Drehbuchautor, Fernseh- und Filmproduzent und der Schöpfer von "Star Trek (Raumschiff Enterprise)".