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Pallasites
The pallasites are a Meteorite classification#Terminology, class of stony–iron meteorite. Structure and composition It consists of centimetre-sized olivine crystals of peridot quality in an iron-nickel Matrix (geology), matrix. Coarser metal areas develop Widmanstätten patterns upon etching. Minor constituents are schreibersite, troilite, chromite, pyroxenes, and phosphates (whitlockite, stanfieldite, farringtonite, and merrillite). Classification and subgroups Using the oxygen isotopic composition, meteoric iron composition and silicate composition pallasites are divided into 4 subgroups:O. Richard Norton. ''The Cambridge encyclopedia of meteorites''. Cambridge, Cambridge University Press, 2002. . * Pallasite main group, Main group pallasites (PMG): Almost all pallasites * Eagle Station group (PES): 5 specimens known. They are related to IIF irons. * Pyroxene Pallasite grouplet (PPX): Counts only Vermillion meteorite, Vermillion and Yamato 8451. They take their name from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eagle Station Group
The Eagle Station group (abbreviated PES - Pallasite Eagle Station) is a set of pallasite meteorite specimen that don't fit into any of the other defined pallasite groups. In meteorite classification five meteorites have to be found, so they can be defined as their own group. Currently only five Eagle Station type meteorites have been found, which is just enough for a separate group. Naming and history The Eagle Station group is named after the Eagle Station meteorite, the type specimen of the group. It is in turned named after Eagle Station, Carroll County Kentucky where it was found. Description The Eagle Station group has a composition similar to Main group pallasites. Diagnostic differences are that the olivine is richer in iron and calcium. The group also has a distinct oxygen isotope signature. The meteoric iron is similar to the IIF iron meteorites. This might indicate that Eagle station group and IIF formed close to each other in the solar nebula. Parent body The t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stony–iron Meteorite
Stony-iron meteorites or siderolites are meteorites that consist of nearly equal parts of meteoric iron and silicates. This distinguishes them from the stony meteorites, that are mostly silicates, and the iron meteorites, that are mostly meteoric iron. Stony-iron meteorites are all differentiated, meaning that they show signs of alteration. They are therefore achondrites. The stony-irons are divided into mesosiderites and pallasites. Pallasites have a matrix of meteoric iron with embedded silicates (most of it olivine). Mesosiderites are breccias which show signs of metamorphism. The meteoric iron occurs in clasts instead of a matrix.Karl K. Turekian. ''Meteorites, comets, and planets'112/ref> They are in the top rank of all Meteorite classification schemes, usually called "Type". Mineralogy The meteoric iron of stony-irons is similar to that of iron meteorites, consisting mostly of kamacite and taenite in different proportions. The silicates are dominated by olivine. Accessor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pallasite Main Group
Almost all pallasite meteorite A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon. When the original object ...s are part of the pallasite main group. References Meteorite groups {{Meteorite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermillion Meteorite
The Vermillion meteorite is a pallasite ( stony-iron) meteorite and one of two members of the pyroxene pallasite grouplet. Discovery The meteorite was found near and was named after Vermillion, Marshall County, Kansas. It was found by two farmers while planting on a grain field in 1991. It was recognized as a meteorite and first described in 1995. Mineralogy Vermillion meteorite consists of around 86volume-% meteoric iron and 14% silicate minerals. The silicates include olivine (93% of silicates), orthopyroxene (5%), chromite (1.5%) and merrillite (0.5%). Other accessory minerals include troilite, whitlockite, and cohenite. Classification The Vermillion meteorite is classified as a pyroxene pallasite because it contains pyroxene as an accessory mineral and shares a distinct oxygen isotope signature with Yamato 8451. Some studies also object to this grouping, referring to the differences in siderophile trace elements and the occurrence of cohenite in the Vermillion meteorit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite Classification
In meteoritics, a meteorite classification system attempts to group similar meteorite, meteorites and allows scientists to communicate with a standardized terminology when discussing them. Meteorites are classified according to a variety of characteristics, especially mineralogy, mineralogical, petrology, petrological, chemistry, chemical, and isotope, isotopic properties. Terminology There is no single, standardized terminology used in meteorite classification; however, commonly used terms for categories include ''types'', ''classes'', ''clans'', ''groups'', and ''subgroups''. Some researchers hierarchize these terms, but there is no consensus as to which hierarchy is most appropriate. Meteorites that do not fit any known group (though they may fit somewhere within a higher level of classification) are ''ungrouped''. Genetic relationships Meteorite classification may indicate that a "genetic" relationship exists between similar meteorite specimens. Similarly classified meteorit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical 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 endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as molar percentages of forsterite (Fo) and fayalite (Fa) (''e.g.'', Fo70Fa30). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. Of the roughly one million known asteroids the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 AU from the Sun, in the main asteroid belt. Asteroids are generally classified to be of three types: C-type, M-type, and S-type. These were named after and are generally identified with carbonaceous, metallic, and silicaceous compositions, respectively. The size of asteroids varies greatly; the largest, Ceres, is almost across and qualifies as a dwarf planet. The total mass of all the asteroids combined is only 3% that of Earth's Moon. The majority of main belt asteroids follow slightly elliptical, stable orbits, revolving in the same direction as the Earth and taking from three to six years to comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yamato 8451
was originally the area around today's Sakurai City in Nara Prefecture of Japan, which became Yamato Province and by extension a name for the whole of Japan. Yamato is also the dynastic name of the ruling Imperial House of Japan. Japanese history * Yamato people, the dominant ethnic group of Japan * Yamato period, when the Japanese Imperial court ruled from Yamato Province * Yamato clan, clan active in Japan since the Kofun period * ''Yamato-damashii'', the "Japanese spirit", or ''Yamato-gokoro'', the "Japanese heart/mind" * Yamato nadeshiko, the ideology of the perfect Japanese woman * Yamato Takeru, a legendary Japanese prince of the Yamato dynasty * Yamato-e, classical Japanese painting * ''Yamato-uta'', alternative term for Waka (poetry), ''waka'' (poetry) * Yamatai, ancient geographical term that may be associated with Yamato * Daiwa (other) is spelled using the same kanji as Yamato Geography Japan * Yamato Province, Japan, former province, present-day Nara Pref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthopyroxene
The pyroxenes (commonly abbreviated to ''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 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 words for 'fire' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter Simon Pallas
Peter Simon Pallas Fellow of the Royal Society, FRS FRSE (22 September 1741 – 8 September 1811) was a Prussian zoologist and botanist who worked in Russia between 1767 and 1810. Life and work Peter Simon Pallas was born in Berlin, the son of Professor of Surgery Simon Pallas. He studied with private tutors and took an interest in natural history, later attending the University of Halle and the University of Göttingen. In 1760, he moved to the University of Leiden and passed his doctor's degree at the age of 19. Pallas travelled throughout the Netherlands and to London, improving his medical and surgical knowledge. He then settled at The Hague, and his new system of animal classification was praised by Georges Cuvier. Pallas wrote ''Miscellanea Zoologica'' (1766), which included descriptions of several vertebrates new to science which he had discovered in the Dutch museum collections. A planned voyage to southern Africa and the East Indies fell through when his father reca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krasnojarsk Meteorite Old
Krasnoyarsk ( ; rus, Красноя́рск, a=Ru-Красноярск2.ogg, p=krəsnɐˈjarsk) (in semantic translation - Red Ravine City) is the largest city and administrative center of Krasnoyarsk Krai, Russia. It is situated along the Yenisey River, and is the second-largest city in Siberia after Novosibirsk, with a population of over 1.1 million. Krasnoyarsk is an important junction of the renowned Trans-Siberian Railway, and is one of the largest producers of aluminium in the country. The city is known for its natural landscape; author Anton Chekhov judged Krasnoyarsk to be the most beautiful city in Siberia. The Stolby Nature Sanctuary is located 10 km south of the city. Krasnoyarsk is a major educational centre in Siberia, and hosts the Siberian Federal University. In 2019, Krasnoyarsk was the host city of the 2019 Winter Universiade, the third hosted in Russia. Geography The total area of the city, including suburbs and the river, is .Poexaly.ru. Krasnoyarsk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2 Pallas
Pallas (minor-planet designation: 2 Pallas) is the second asteroid to have been discovered, after Ceres. It is believed to have a mineral composition similar to carbonaceous chondrite meteorites, like Ceres, though significantly less hydrated than Ceres. It is the third-largest asteroid in the Solar System by both volume and mass, and is a likely remnant protoplanet. It is 79% the mass of Vesta and 22% the mass of Ceres, constituting an estimated 7% of the mass of the asteroid belt. Its estimated volume is equivalent to a sphere in diameter, 90–95% the volume of Vesta. During the planetary formation era of the Solar System, objects grew in size through an accretion process to approximately the size of Pallas. Most of these protoplanets were incorporated into the growth of larger bodies, which became the planets, whereas others were ejected by the planets or destroyed in collisions with each other. Pallas, Vesta and Ceres appear to be the only intact bodies from this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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