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951 Gaspra
951 Gaspra is an S-type asteroid, S-type asteroid that orbits very close to the inner edge of the asteroid belt. Gaspra was discovered by Russian astronomer G. N. Neujmin in 1916. Neujmin named it after Gaspra, a Black Sea retreat that was visited by his contemporaries, such as Maxim Gorky, Gorky and Tolstoy. Gaspra was the first asteroid ever to be closely approached when it was visited by the ''Galileo spacecraft, Galileo'' spacecraft, which flew by on its way to Jupiter on 29 October 1991. Physical characteristics Apart from a multitude of small craters, Gaspra has half a dozen large flat areas and concavities. One of these flat areas, Dunne Regio, is a area that is flat to within . It is uncertain whether these are the result of impacts or whether they are instead facets formed when Gaspra broke off its parent asteroid. In the weak, lopsided gravity of Gaspra, impact craters would naturally take on such flat, lopsided shapes, making this determination difficult. The flat fac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grigory Neujmin
Grigory Nikolayevich Neujmin (; – 17 December 1946) was a Georgian–Russian astronomer, native of Tbilisi in Georgia (country), Georgia, and a discoverer of numerous minor planets as well as 6 periodic comet, periodic and a List of hyperbolic comets, hyperbolic comet at the Pulkovo Observatory, Pulkovo and Simeiz Observatory, Simeiz Observatories during the first half of the 20th century. Discoveries The Minor Planet Center credits his discoveries under the name "List of minor planet discoverers#G. N. Neujmin, G. N. Neujmin", and his surname appears this way in the literature. However, the modern English transliteration of his name would be Neuymin. Neujmin is credited with the discovery of 74 asteroids, and notably 951 Gaspra and 762 Pulcova. He also discovered and co-discovered 6 Jupiter-family comets, namely 25D/Neujmin, 28P/Neujmin, 42P/Neujmin, 57P/du Toit-Neujmin-Delporte (including List of numbered comets#57P/du Toit–Neujmin–Delporte, fragment A) and 58P/Jackso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). Asteroids are rocky, metallic, or icy bodies with no atmosphere, and are broadly classified into C-type asteroid, C-type (carbonaceous), M-type asteroid, M-type (metallic), or S-type asteroid, S-type (silicaceous). The size and shape of asteroids vary significantly, ranging from small rubble piles under a kilometer across to Ceres (dwarf planet), Ceres, a dwarf planet almost 1000 km in diameter. A body is classified as a comet, not an asteroid, if it shows a coma (tail) when warmed by solar radiation, although recent observations suggest a continuum between these types of bodies. Of the roughly one million known asteroids, the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 astronomical unit, AU ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaspra Phobos Deimos
Gaspra (; ; ; from Greek , 'white'), officially transliterated Haspra, is a spa town, an urban-type settlement in Yalta Municipality in the Autonomous Republic of Crimea. It is located on the Black Sea coast, west of Yalta, and is a popular holiday resort. Population: Leo Tolstoy lived in Gaspra in 1901 and 1902. Nearby are the Swallow's Nest, a modern castle and Charax, Crimea a Roman fort. The asteroid 951 Gaspra is named after the town. History In the 70s of the second century - the first half of the third century, there was a fortress of Haraks (on the site of an ancient Taurian settlement), the largest base of Roman troops in the Crimea. In the Middle Ages, it was a zone of Greek colonization (Gaspra from the Greek "aspro" - white). It has been known as a settlement since the mid-eighteenth century. After the Crimean Khanate was incorporated into the Russian Empire (1783), the lands around Gaspra were distributed to Russian aristocrats (including members of the roy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroxene
The pyroxenes (commonly abbreviated Px) are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes have the general formula , where X represents ions of calcium (Ca), sodium (Na), iron (Fe(II)) or magnesium (Mg) and more rarely zinc, manganese or lithium, and Y represents ions of smaller size, such as chromium (Cr), aluminium (Al), magnesium (Mg), cobalt (Co), manganese (Mn), scandium (Sc), titanium (Ti), vanadium (V) or even iron (Fe(II) or Fe(III)). Although aluminium substitutes extensively for silicon in silicates such as feldspars and amphiboles, the substitution occurs only to a limited extent in most pyroxenes. They share a common structure consisting of single chains of silica tetrahedra. Pyroxenes that crystallize in the monoclinic system are known as clinopyroxenes and those that crystallize in the orthorhombic system are known as orthopyroxenes. The name ''pyroxene'' is derived from the Ancient Greek w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olivine
The mineral olivine () is a magnesium iron Silicate minerals, silicate with the chemical formula . It is a type of Nesosilicates, nesosilicate or orthosilicate. The primary component of the Earth's upper mantle (Earth), upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. Olivine has many uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmember (mineralogy), endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as Mole (unit), molar percentages of forsterite (Fo) and/or fayalite (Fa) (''e.g.'', Fo70Fa30, or just Fo70 with Fa30 implied). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while fayalite's is much lower – about . Melting temperature varies smoothly between the two end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hong Kong
Hong Kong)., Legally Hong Kong, China in international treaties and organizations. is a special administrative region of China. With 7.5 million residents in a territory, Hong Kong is the fourth most densely populated region in the world. Hong Kong was established as a colony of the British Empire after the Qing dynasty ceded Hong Kong Island in 1841–1842 as a consequence of losing the First Opium War. The colony expanded to the Kowloon Peninsula in 1860 and was further extended when the United Kingdom obtained a 99-year lease of the New Territories in 1898. Hong Kong was occupied by Japan from 1941 to 1945 during World War II. The territory was handed over from the United Kingdom to China in 1997. Hong Kong maintains separate governing and economic systems from that of mainland China under the principle of one country, two systems. Originally a sparsely populated area of farming and fishing villages,. the territory is now one of the world's most signific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guam
Guam ( ; ) is an island that is an Territories of the United States, organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. Guam's capital is Hagåtña, Guam, Hagåtña, and the most populous village is Dededo. It is the List of extreme points of the United States#Westernmost points, westernmost point and territory of the United States, as measured from the geographic center of the United States, geographic center of the U.S. In Oceania, Guam is the largest and southernmost of the Mariana Islands and the largest island in Micronesia. As of 2022, its population was 168,801. Chamorros are its largest ethnic group, but a minority on the multiethnic island. The territory spans and has a population density of . Indigenous Guamanians are the Chamorro people, Chamorro, who are related to the Austronesian peoples, Austronesian peoples of the Malay Archipelago, the Philippines, Taiwanese indigenous peoples, Taiwan, and Polyne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impact Crater
An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, 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. Impact craters are typically circular, though they can be elliptical in shape or even irregular due to events such as landslides. Impact craters range in size from microscopic craters seen on lunar rocks returned by the Apollo Program to simple bowl-shaped depressions and vast, 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 (planet), Mercury, Callisto (moon), Callisto, Ganymede (moon), Ganymede, and most small moons and asteroids. On other planet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity
In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force between objects and the Earth. This force is dominated by the combined gravitational interactions of particles but also includes effect of the Earth's rotation. Gravity gives weight to physical objects and is essential to understanding the mechanisms responsible for surface water waves and lunar tides. Gravity also has many important biological functions, helping to guide the growth of plants through the process of gravitropism and influencing the circulation of fluids in multicellular organisms. The gravitational attraction between primordial hydrogen and clumps of dark matter in the early universe caused the hydrogen gas to coalesce, eventually condensing and fusing to form stars. At larger scales this results in galaxies and clust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. Its diameter is 11 times that of Earth and a tenth that of the Sun. Jupiter orbits the Sun at a distance of , with an orbital period of . It is the List of brightest natural objects in the sky, third-brightest natural object in the Earth's night sky, after the Moon and Venus, and has been observed since prehistoric times. Its name derives from that of Jupiter (god), Jupiter, the chief deity of ancient Roman religion. Jupiter was the first of the Sun's planets to form, and its inward migration during the primordial phase of the Solar System affected much of the formation history of the other planets. Jupiter's atmosphere consists of 76% hydrogen and 24% helium by mass, with a denser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galileo Spacecraft
''Galileo'' was an American robotic space probe that studied the planet Jupiter and its moons, as well as the asteroids Gaspra and Ida. Named after the Italian astronomer Galileo Galilei, it consisted of an orbiter and an entry probe. It was delivered into Earth orbit on October 18, 1989, by , during STS-34. ''Galileo'' arrived at Jupiter on December 7, 1995, after gravitational assist flybys of Venus and Earth, and became the first spacecraft to orbit an outer planet. The Jet Propulsion Laboratory built the ''Galileo'' spacecraft and managed the ''Galileo'' program for NASA. West Germany's Messerschmitt-Bölkow-Blohm supplied the propulsion module. NASA's Ames Research Center managed the atmospheric probe, which was built by Hughes Aircraft Company. At launch, the orbiter and probe together had a mass of and stood tall. Spacecraft are normally stabilized either by spinning around a fixed axis or by maintaining a fixed orientation with reference to the Sun and a star. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tolstoy
Count Lev Nikolayevich Tolstoy Tolstoy pronounced his first name as , which corresponds to the romanization ''Lyov''. () (; ,Throughout Tolstoy's whole life, his name was written as using pre-reform Russian orthography. ; ), usually referred to in English as Leo Tolstoy, was a Russian writer. He is regarded as one of the greatest and most influential authors of all time. Born to an aristocratic family, Tolstoy achieved acclaim in his twenties with his semi-autobiographical trilogy, ''Childhood'', '' Boyhood'' and ''Youth'' (1852–1856), and with ''Sevastopol Sketches'' (1855), based on his experiences in the Crimean War. His '' War and Peace'' (1869), '' Anna Karenina'' (1878), and ''Resurrection'' (1899), which is based on his youthful sins, are often cited as pinnacles of realist fiction and three of the greatest novels ever written. His ''oeuvre'' includes short stories such as " Alyosha the Pot" (1911) and " After the Ball" (1911) and novellas such as '' Family Happi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
