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Palimpsest (planetary Astronomy)
A palimpsest , in planetary astronomy, is an ancient crater that has been degraded over time. They may also be referred to as "ghost craters", "degraded craters", "buried craters", or "pathological craters". Palimpsests have been identified on Mercury, the Earth, the Moon, Mars, Ganymede, Callisto, and possibly even Titan. On Mars, these features are morphologically described as craters that are "flat-floored, rimless, extremely shallow, without central peaks, and would probably represent what remains after erosion." On an icy moon of the outer Solar System, a palimpsest is a crater whose relief has disappeared due to creep of the icy surface ("viscous relaxation") or subsequent cryovolcanic outpourings, leaving a circular albedo feature, perhaps with a "ghost" of a rim. Icy surfaces of natural satellites like Callisto Callisto most commonly refers to: *Callisto (mythology), a nymph *Callisto (moon), a moon of Jupiter Callisto may also refer to: Art and entertainment *''Call ...
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Memphis Facula
Memphis Facula is a palimpsest, or "ghost crater", on Ganymede, the largest of the Jovian satellites. About 360 km across, it is situated in the southwestern part of Galileo Regio, a huge almost circular dark region in Ganymede's northern hemisphere. Although almost level today, it is a relic of a massive impact and once was a deep impact crater whose walls have slumped and its floor has risen isostatically, smoothing out the remaining topography with slush. The morphology of the larger palimpsests like Memphis Facula suggests that Ganymede's icy crust at the time of impact was about 10 km thick and was penetrated by the impact, allowing the slush and fluid beneath to fill and level out the crater. See also *Ganymede City ''3001: The Final Odyssey'' is a 1997 science fiction novel by British writer Arthur C. Clarke. It is the fourth and final book in Clarke's ''Space Odyssey'' series. Plot summary The novel begins with a brief prologue describing th ...
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Planetary Science
Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets) and planetary systems (in particular those of the Solar System) and the processes of their formation. It studies objects ranging in size from micrometeoroids to gas giants, aiming to determine their composition, dynamics, formation, interrelations and history. It is a strongly interdisciplinary field, which originally grew from astronomy and Earth science, and now incorporates many disciplines, including planetary geology, cosmochemistry, atmospheric science, physics, oceanography, hydrology, theoretical planetary science, glaciology, and exoplanetology. Allied disciplines include space physics, when concerned with the effects of the Sun on the bodies of the Solar System, and astrobiology. There are interrelated observational and theoretical branches of planetary science. Observational research can involve combinations of spac ...
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Impact Crater
An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Lunar impact craters range from microscopic craters on lunar rocks returned by the Apollo Program and small, simple, bowl-shaped depressions in the lunar regolith to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including the Moon, Mercury, Callisto, Ganymede and most small moons and asteroids. On other planets and moons that experience more active surface geological processes, such as Earth, Venus, Europa, Io and Titan, visible impact craters are less common because they become eroded ...
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Icy Moon
Icy commonly refers to conditions involving ice, a frozen state, usually referring to frozen water. Icy or Icey may also refer to: People * Icy Spicy Leoncie, an Icelandic-Indian musician Arts, entertainment, and media Music * ICY (band), a vocalist trio * "Icy" (Itzy song), 2019 * "Icy" (Gucci Mane song), 2005 * "Icy", a song by Kim Petras from the album ''Clarity'', 2019 * "Icy", a song by Logic from the album '' Confessions of a Dangerous Mind'', 2019 * "Icy", a song by Vain from the album ''No Respect'', 1989 * "Icey", a song by Young Thug from the EP ''On the Rvn'', 2018 Other * ''Icey'', a 2016 video game * Icy, a member of the Trix in the fictional series ''Winx Club'' Other uses * Icy (application), a package manager for iPhone OS * iCy, a penguin toy that is similar to the iDog See also * The Icee Company, makers of ICEE frozen carbonated beverage * IcyHot, a brand of liniments * ICEE (other) ICEE may refer to: Conferences *International Conference on Elect ...
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Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ...
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Relief
Relief is a sculptural method in which the sculpted pieces are bonded to a solid background of the same material. The term ''relief'' is from the Latin verb ''relevo'', to raise. To create a sculpture in relief is to give the impression that the sculpted material has been raised above the background plane. When a relief is carved into a flat surface of stone (relief sculpture) or wood (relief carving), the field is actually lowered, leaving the unsculpted areas seeming higher. The approach requires a lot of chiselling away of the background, which takes a long time. On the other hand, a relief saves forming the rear of a subject, and is less fragile and more securely fixed than a sculpture in the round, especially one of a standing figure where the ankles are a potential weak point, particularly in stone. In other materials such as metal, clay, plaster stucco, ceramics or papier-mâché the form can be simply added to or raised up from the background. Monumental bronze reliefs a ...
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Cryovolcanic
A cryovolcano (sometimes informally called an ice volcano) is a type of volcano that erupts volatiles such as water, ammonia or methane into an extremely cold environment that is at or below their freezing point. The process of formation is known as cryovolcanism. Collectively referred to as cryomagma, cryolava or ice-volcanic melt, these substances are usually liquids and can form plumes, but can also be in vapour form. After the eruption, cryomagma is expected to condense to a solid form when exposed to the very low surrounding temperature. Cryovolcanoes may potentially form on icy moons and other objects with abundant water past the Solar System's snow line (such as Pluto). A number of features have been identified as possible cryovolcanoes on Pluto, Titan and Ceres, and a subset of domes on Europa may have cryovolcanic origins. In addition, although they are not known to form volcanoes, ice geysers have been observed on Enceladus and potentially Triton. One potential en ...
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Callisto (moon)
Callisto (), or Jupiter IV, is the second-largest moon of Jupiter, after Ganymede. It is the third-largest moon in the Solar System after Ganymede and Saturn's largest moon Titan, and the largest object in the Solar System that may not be properly differentiated. Callisto was discovered in 1610 by Galileo Galilei. With a diameter of , Callisto is about 99% the diameter of the planet Mercury, but only about a third of its mass. It is the fourth Galilean moon of Jupiter by distance, with an orbital radius of about . It is not in an orbital resonance like the three other Galilean satellites— Io, Europa, and Ganymede—and is thus not appreciably tidally heated. Callisto's rotation is tidally locked to its orbit around Jupiter, so that the same hemisphere always faces inward. Because of this, there is a sub-Jovian point on Callisto's surface, from which Jupiter would appear to hang directly overhead. It is less affected by Jupiter's magnetosphere than the other inner satell ...
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Ganymede (moon)
Ganymede, a satellite of Jupiter (Jupiter III), is the largest and most massive of the Solar System's moons. The ninth-largest object (including the Sun) of the Solar System, it is the largest without a substantial atmosphere (albeit not the most massive one, which is Mercury). It has a diameter of , making it 26 percent larger than the planet Mercury by volume, although it is only 45 percent as massive. Possessing a metallic core, it has the lowest moment of inertia factor of any solid body in the Solar System and is the only moon known to have a magnetic field. Outward from Jupiter, it is the seventh satellite and the third of the Galilean moons, the first group of objects discovered orbiting another planet. Ganymede orbits Jupiter in roughly seven days and is in a 1:2:4 orbital resonance with the moons Europa and Io, respectively. Ganymede is composed of approximately equal amounts of silicate rock and water. It is a fully differentiated body with an iron-rich, liq ...
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Palimpsest (geology)
In geology, a palimpsest is a geographical feature composed of superimposed structures created at different times. Palimpsest is beginning to be used by glaciologists to describe contradicting glacial flow indicators, usually consisting of smaller indicators (i.e., striae) overprinted upon larger features (i.e., stoss and lee topography, drumlins, etc.). The name arises by analogy to a medieval palimpsest In textual studies, a palimpsest () is a manuscript page, either from a scroll or a book, from which the text has been scraped or washed off so that the page can be reused for another document. Parchment was made of lamb, calf, or kid skin an ..., a reused parchment manuscript page in which the previous text can sometimes be deciphered. See also * Palimpsest (planetary astronomy) * Palimpsest (other) Glaciology Paleogeography {{glaciology-stub ...
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Ghost Craters On Mercury
Ghost craters on the planet Mercury have tectonic features such as graben and wrinkle ridges. These features were formed by extensional and contractional forces originating in tectonic processes such as uplift and global contraction. The combination of graben and wrinkle ridges inside ghost craters found on Mercury has not been observed on any of the other terrestrial planets. Discovery The tectonic features on Mercury were not studied in precise detail until the ''MESSENGER'' spacecraft was sent to Mercury; by 2009 the ''MESSENGER'' spacecraft had mapped 98% of the planet's surface. By 2013, Messenger mapped 100% of the planet's surface. Mercury Dual Imaging System cameras and Mercury Laser Altimeter equipment on the messenger spacecraft allowed for researchers to obtain high-resolution images of the planet's surface for analyzing Mercury's tectonics. Ghost craters Ghost craters are impact craters that have been filled with volcanic deposits. Ghost craters can be observed on ...
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Springer Science+Business Media
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology
". Springer Science+Business Media.
In 1964, Springer expanded its business internationally, o ...
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