1.
Jupiter
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Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a giant planet with a mass one-thousandth that of the Sun, Jupiter and Saturn are gas giants, the other two giant planets, Uranus and Neptune are ice giants. Jupiter has been known to astronomers since antiquity, the Romans named it after their god Jupiter. Jupiter is primarily composed of hydrogen with a quarter of its mass being helium and it may also have a rocky core of heavier elements, but like the other giant planets, Jupiter lacks a well-defined solid surface. Because of its rotation, the planets shape is that of an oblate spheroid. The outer atmosphere is visibly segregated into several bands at different latitudes, resulting in turbulence, a prominent result is the Great Red Spot, a giant storm that is known to have existed since at least the 17th century when it was first seen by telescope. Surrounding Jupiter is a faint planetary ring system and a powerful magnetosphere, Jupiter has at least 67 moons, including the four large Galilean moons discovered by Galileo Galilei in 1610. Ganymede, the largest of these, has a greater than that of the planet Mercury. Jupiter has been explored on several occasions by robotic spacecraft, most notably during the early Pioneer and Voyager flyby missions and later by the Galileo orbiter. In late February 2007, Jupiter was visited by the New Horizons probe, the latest probe to visit the planet is Juno, which entered into orbit around Jupiter on July 4,2016. Future targets for exploration in the Jupiter system include the probable ice-covered liquid ocean of its moon Europa, Earth and its neighbor planets may have formed from fragments of planets after collisions with Jupiter destroyed those super-Earths near the Sun. Astronomers have discovered nearly 500 planetary systems with multiple planets, Jupiter moving out of the inner Solar System would have allowed the formation of inner planets, including Earth. Jupiter is composed primarily of gaseous and liquid matter and it is the largest of the four giant planets in the Solar System and hence its largest planet. It has a diameter of 142,984 km at its equator, the average density of Jupiter,1.326 g/cm3, is the second highest of the giant planets, but lower than those of the four terrestrial planets. Jupiters upper atmosphere is about 88–92% hydrogen and 8–12% helium by percent volume of gas molecules, a helium atom has about four times as much mass as a hydrogen atom, so the composition changes when described as the proportion of mass contributed by different atoms. Thus, Jupiters atmosphere is approximately 75% hydrogen and 24% helium by mass, the atmosphere contains trace amounts of methane, water vapor, ammonia, and silicon-based compounds. There are also traces of carbon, ethane, hydrogen sulfide, neon, oxygen, phosphine, the outermost layer of the atmosphere contains crystals of frozen ammonia. The interior contains denser materials - by mass it is roughly 71% hydrogen, 24% helium, through infrared and ultraviolet measurements, trace amounts of benzene and other hydrocarbons have also been found
2.
Europa (moon)
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Europa /jʊˈroʊpə/, is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet. 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 legendary mother of King Minos of Crete and lover of Zeus. Slightly smaller than Earths Moon, Europa is primarily made of rock and has a water-ice crust. It has an atmosphere composed primarily of oxygen. Its surface is striated by cracks and streaks, whereas craters are relatively rare, in addition to Earth-bound telescope observations, Europa has been examined by a succession of space probe flybys, the first occurring in the early 1970s. Europa has the smoothest surface of any solid object in the Solar System. The apparent youth and smoothness of the surface have led to the hypothesis that a water ocean exists beneath it, sea salt from a subsurface ocean may 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, in addition, the Hubble Space Telescope detected water vapor plumes similar to those observed on Saturns moon Enceladus, which are thought to be caused by erupting cryogeysers. The Galileo mission, launched in 1989, provides the bulk of current data on Europa, no spacecraft has yet landed on Europa, although there have been several proposed exploration missions. The European Space Agencys Jupiter Icy Moon Explorer is a mission to Ganymede that is due to launch in 2022, NASAs planned Europa Multiple-Flyby Mission will be launched in the mid-2020s. Europa, along with Jupiters 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 Galilei on 7 January 1610 using a 20×-magnification refracting telescope at the University of Padua. However, in observation, Galileo could not separate Io and Europa due to the low magnification of his telescope. The following day,8 January 1610, Io and Europa were seen for the first time as separate bodies during Galileos 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, Europa was courted by Zeus and became the queen of Crete. The naming scheme was suggested by Simon Marius, who discovered the four satellites independently, Marius attributed the proposal to Johannes Kepler. The names fell out of favor for a time and were not revived in general use until the mid-20th century. In much of the astronomical literature, Europa is simply referred to by its Roman numeral designation as Jupiter II or as the second satellite of Jupiter
3.
Lightcurve
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In astronomy, a light curve is a graph of light intensity of a celestial object or region, as a function of time. The light is usually in a particular frequency interval or band, the study of the light curve, together with other observations, can yield considerable information about the physical process that produces it or constrain the physical theories about it. Light waves can also be used in botany to determine a plants reactions to light intensities, in astronomy, light curves from a supernova are used to determine what type of supernova it is. If the supernovas light curve has a maximum and slopes down gradually. If the supernovas light curve has a sharp maximum, slopes down quickly. In planetary science, a curve can be used to derive the rotation period of a minor planet, moon. Thus, astronomers measure the amount of produced by an object as a function of time. The time separation of peaks in the curve gives an estimate of the rotational period of the object. The difference between the maximum and minimum brightnesses can be due to the shape of the object, or to bright, for example, an asymmetrical asteroids light curve generally has more pronounced peaks, while a more spherical objects light curve will be flatter. The Asteroid Lightcurve Database of the Collaborative Asteroid Lightcurve Link uses a code to assess the quality of a period solution for minor planet light curves. Its quality code parameter U ranges from 0 to 3, U =0 → Result later proven incorrect U =1 → Result based on fragmentary light curve, U =2 → Result based on less than full coverage. Period may be wrong by 30 percent or ambiguous, U =3 → Secure result within the precision given. A trailing plus sign or minus sign is used to indicate a slightly better or worse quality than the unsigned value. In botany, a light curve shows the response of leaf tissue or algal communities to varying light intensities. Since photosynthesis is limited by ambient carbon dioxide levels, light curves are often repeated at several different constant carbon dioxide concentrations. The AAVSO online light curve generator can plot light curves for thousands of variable stars Lightcurves, An Introduction by NASAs Imagine the Universe
4.
Hermann Goldschmidt
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Hermann Mayer Salomon Goldschmidt was a German-French astronomer and painter who spent much of his life in France. He started out as a painter, but after attending a lecture by the famous French astronomer Urbain Le Verrier turned to astronomy and his discovery of the asteroid Lutetia in 1852 was followed by further findings and by 1861 Goldschmidt had discovered 14 asteroids. He received the Gold Medal of the Royal Astronomical Society in 1861 for having discovered more asteroids than any other person up to that time and he died from complications of diabetes. Goldschmidt was born in Frankfurt as the son of a Jewish merchant, during a journey to the Netherlands, Goldschmidt visited Dutch picture galleries. The impression of this convinced him to become a painter. He studied art in Munich for several years under supervision of famous painters as Peter von Cornelius and Julius Schnorr von Carolsfeld. To complete his education, in 1836 Goldschmidt went to Paris, in 1820, Goldschmidt discovered shadow bands in total solar eclipses. Several lectures on astronomy were planned for the occasion of the eclipse of March 31,1847. Urbain Le Verrier, discoverer of Neptune, held one in the Sorbonne, by pure chance, Goldshmidt attended this lecture, which awakened his interest in astronomy and led him to pursue it as a career. Goldschmidt bought a telescope with the diameter of 23 lines with the money he got from selling two portraits of Galileo he painted during a stay in Florence, Goldschmidt set up the telescope in his apartment on the sixth floor above the Café Procope. Very soon he started updating the Star charts he had with new stars, during this work he observed the same area several times and was able to detect variable stars and moving objects like planets. He discovered his first new planet on November 15,1852, Goldschmidt confirmed his observations with the help of François Arago at the Paris Observatory on November 18. Arago suggested the name Lutetium, based on the Latin name of Paris Lutetia used during the Roman occupation, the discovery of the new planet was published on November 23. In subsequent years, Goldschmidt bought larger telescopes, one with 30 lines diameter, despite the limited observational capabilities of his instrument, which was inferior to those of most of his competitors, by May 1856 Goldschmidt had discovered four more asteroids. His next telescope was one with the diameter of 4 inches and this technical improvement enabled him to discover nine asteroids between May 1857 and May 1861. During that period, the Academy of Science awarded Goldschmidt the astronomical prize medal several times, by the time of his final discovery in May 1861, the Royal Astronomical Society had awarded him the Gold Medal of the Royal Astronomical Society for the discovery of 13 asteroids. At that point, the second most successful astronomers John Russell Hind, Goldschmidt combined his abilities as a painter with his love for astronomy as exemplified by his paintings of the Great Comet of 1858 and of the solar eclipse he observed in Spain July 1860. In April 1861, he announced the discovery of a moon of Saturn between Titan and Hyperion, which he named Chiron
5.
Europa (mythology)
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In Greek mythology Europa was the mother of King Minos of Crete, a woman with Phoenician origin of high lineage, and for whom the continent Europe was named. This can especially be said of the story of Europa, Europas earliest literary reference is in the Iliad, which is commonly dated to the 8th century BC. Another early reference to her is in a fragment of the Hesiodic Catalogue of Women, the earliest vase-painting securely identifiable as Europa dates from mid-7th century BC. Greek Εὐρώπη Eurṓpē contains the elements εὐρύς, wide, broad and ὤψ/ὠπ-/ὀπτ- eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion. It is common in ancient Greek mythology and geography to identify lands or rivers with female figures, thus, Europa is first used in a geographic context in the Homeric Hymn to Delian Apollo, in reference to the western shore of the Aegean Sea. As a name for a part of the world, it is first used in the 6th century BC by Anaximander. Barry adduces the word Ereb on an Assyrian stele with the meaning of night, sunset, in opposition to Asu sunrise and this proposal is mostly considered unlikely or untenable. They call it the temple of Astarte, I hold this Astarte to be no other than the moon-goddess. But according to the story of one of the priests this temple is sacred to Europa and this legend I heard from other Phœnicians as well, and the coinage current among the Sidonians bears upon it the effigy of Europa sitting upon a bull, none other than Zeus. Thus they do not agree that the temple in question is sacred to Europa, the paradox, as it seemed to Lucian, would be solved if Europa is Astarte in her guise as the full, broad-faced moon. Sources differ in details regarding Europas family, but agree that she is Phoenician, and from a lineage that descended from Io, the mythical nymph beloved of Zeus, who was transformed into a heifer. She is generally said to be the daughter of Agenor, the Phoenician King of Tyre, other sources, such as the Iliad, claim that she is the daughter of Agenors son, the sun-red Phoenix. So some interpret this as her brother Phoenix gave his siblings name to his three children and this Europa is also loved by Zeus, but because of the same name, gave some confusions to others. After arriving in Crete, Europa had three sons fathered by Zeus, Minos, Rhadamanthus, and Sarpedon, the three of whom became the three judges of the Underworld when they died, in Crete she married Asterion also rendered Asterius and became mother of his daughter Crete. There were two competing myths relating how Europa came into the Hellenic world, but they agreed that she came to Crete, the mythical Europa cannot be separated from the mythology of the sacred bull, which had been worshipped in the Levant. There is also a sanctuary of Demeter Europa, the mythographers tell that Zeus was enamored of Europa and decided to seduce or ravish her, the two being near-equivalent in Greek myth. He transformed himself into a white bull and mixed in with her fathers herds. While Europa and her helpers were gathering flowers, she saw the bull, caressed his flanks, Zeus took that opportunity and ran to the sea and swam, with her on his back, to the island of Crete
6.
Minor planet
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A minor planet is an astronomical object in direct orbit around the Sun that is neither a planet nor exclusively classified as a comet. Minor planets can be dwarf planets, asteroids, trojans, centaurs, Kuiper belt objects, as of 2016, the orbits of 709,706 minor planets were archived at the Minor Planet Center,469,275 of which had received permanent numbers. The first minor planet to be discovered was Ceres in 1801, the term minor planet has been used since the 19th century to describe these objects. The term planetoid has also used, especially for larger objects such as those the International Astronomical Union has called dwarf planets since 2006. Historically, the asteroid, minor planet, and planetoid have been more or less synonymous. This terminology has become complicated by the discovery of numerous minor planets beyond the orbit of Jupiter. A Minor planet seen releasing gas may be classified as a comet. Before 2006, the IAU had officially used the term minor planet, during its 2006 meeting, the IAU reclassified minor planets and comets into dwarf planets and small Solar System bodies. Objects are called dwarf planets if their self-gravity is sufficient to achieve hydrostatic equilibrium, all other minor planets and comets are called small Solar System bodies. The IAU stated that the minor planet may still be used. However, for purposes of numbering and naming, the distinction between minor planet and comet is still used. Hundreds of thousands of planets have been discovered within the Solar System. The Minor Planet Center has documented over 167 million observations and 729,626 minor planets, of these,20,570 have official names. As of March 2017, the lowest-numbered unnamed minor planet is 1974 FV1, as of March 2017, the highest-numbered named minor planet is 458063 Gustavomuler. There are various broad minor-planet populations, Asteroids, traditionally, most have been bodies in the inner Solar System. Near-Earth asteroids, those whose orbits take them inside the orbit of Mars. Further subclassification of these, based on distance, is used, Apohele asteroids orbit inside of Earths perihelion distance. Aten asteroids, those that have semi-major axes of less than Earths, Apollo asteroids are those asteroids with a semimajor axis greater than Earths, while having a perihelion distance of 1.017 AU or less. Like Aten asteroids, Apollo asteroids are Earth-crossers, amor asteroids are those near-Earth asteroids that approach the orbit of Earth from beyond, but do not cross it
7.
Asteroid belt
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The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets, the asteroid belt is also termed the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System such as near-Earth asteroids and trojan asteroids. About half the mass of the belt is contained in the four largest asteroids, Ceres, Vesta, Pallas, the total mass of the asteroid belt is approximately 4% that of the Moon, or 22% that of Pluto, and roughly twice that of Plutos moon Charon. Ceres, the belts only dwarf planet, is about 950 km in diameter, whereas Vesta, Pallas. The remaining bodies range down to the size of a dust particle, the asteroid material is so thinly distributed that numerous unmanned spacecraft have traversed it without incident. Nonetheless, collisions between large asteroids do occur, and these can form a family whose members have similar orbital characteristics. Individual asteroids within the belt are categorized by their spectra. The asteroid belt formed from the solar nebula as a group of planetesimals. Planetesimals are the precursors of the protoplanets. Between Mars and Jupiter, however, gravitational perturbations from Jupiter imbued the protoplanets with too much energy for them to accrete into a planet. Collisions became too violent, and instead of fusing together, the planetesimals, as a result,99. 9% of the asteroid belts original mass was lost in the first 100 million years of the Solar Systems history. Some fragments eventually found their way into the inner Solar System, Asteroid orbits continue to be appreciably perturbed whenever their period of revolution about the Sun forms an orbital resonance with Jupiter. At these orbital distances, a Kirkwood gap occurs as they are swept into other orbits. Classes of small Solar System bodies in other regions are the objects, the centaurs, the Kuiper belt objects, the scattered disc objects, the sednoids. On 22 January 2014, ESA scientists reported the detection, for the first definitive time, of water vapor on Ceres, the detection was made by using the far-infrared abilities of the Herschel Space Observatory. The finding was unexpected because comets, not asteroids, are considered to sprout jets. According to one of the scientists, The lines are becoming more and more blurred between comets and asteroids. This pattern, now known as the Titius–Bode law, predicted the semi-major axes of the six planets of the provided one allowed for a gap between the orbits of Mars and Jupiter
. Bibcode:2013Icar..225..794M. doi:10.1016/j.icarus.2013.01.010.
