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Compositional differences between meteorites and near-Earth asteroids
Nature, 2008Understanding the nature and origin of the asteroid population in Earth's vicinity (near-Earth asteroids, and its subset of potentially hazardous asteroids) is a matter of both scientific interest and practical importance. It is generally expected that the compositions of the asteroids that are most likely to hit Earth should reflect those of the most ...
Vernazza, P. +7 more
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Meteoritic Nanodiamonds: Alternative Composition of Xenon Components
Solar System Research, 2020For the first time, abundances of the main xenon components (Xe-P3, Xe-P3(fr), Xe-P6 and Xe-pr instead Xe-HL) in the nanodiamonds of Orgueil (CI), Tieschitz (H3.6) and Indarch (EH3-4) meteorites have been calculated. The Xe-pr component is the excess fraction of xenon isotopes in the Xe-HL component relative to Xe-P3 (fr) and mainly consists of the 124,
A. V. Fisenko, L. F. Semjonova
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A compositional classification scheme for meteoritic chondrules
Nature, 1992A compositionally based classification scheme for chondrules is proposed that will help in systematizing the wealth of data available and disentangling the effects of nebular and subsequent processes. The classification is not by texture or the composition of a single phase, or a mixture of these two, but rather is a comprehensive, systematic approach ...
Derek W. G. Sears +4 more
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The Average Composition of Meteoritic Iron*
Contributions of the Society for Research on Meteorites, 1946ABSTRACTAverage analyses are given by type and as a whole for iron meteorites (siderites, Si), based on selected analyses of 327 siderites. Average compositions are given also for pallasites (P), mesosiderites (Ms), and for the metallic part of chondrites (C).
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The composition of the stone meteorites and the origin of the meteorites
Geochimica et Cosmochimica Acta, 1953Abstract A study has been made of some 350 chemical analyses of stone meteorites available in the literature, and criteria have been applied in an attempt to select those which are more reliable. It is found that the chondrites fall into two distinct groups with regard to both the total iron content and the oxidation state of the iron.
Harold C. Urey, Harmon Craig
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Isotopic composition of germanium in meteorites
Journal of Geophysical Research, 1963The isotopic composition of germanium in eight meteorites was measured by solid-source mass spectrometer and compared with a sample of terrestrial origin. No difference in the isotopic composition of germanium from meteorites and the terrestrial sample was found outside of the error. (auth)
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The amphoterites and meteorites of similar composition
Geochimica et Cosmochimica Acta, 1964Abstract The amphoteritos are a subclass of the olivine-hypersthene chondrites characterized by comparatively iron-rich olivine (Fa27–31) and orthopyroxene (Fs23–27) and a low content (1–5%) of nickel-iron. Other minerals include plagioclase (composition around An10), troilite, chromite and a phosphate mineral (apatite and/or merrillite).
Brian Mason, H.B. Wiik
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Iron Meteorites: Composition, Age, and Origin
2020Iron meteorites are thought to be samples of metallic cores and pools that formed in diverse small planetary bodies. Their great diversity offers remarkable insights into the formation of asteroids and the early history of the solar system. The chemical compositions of iron meteorites generally match those predicted from experimental and theoretical ...
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Origin, age, and composition of meteorites
Space Science Reviews, 1964This paper attempts to bring together and evaluate all significant evidence on the origin of meteorites. The iron meteorites seem to have formed at low pressures. Laboratory evidence shows that the absence of a Widmanstatten pattern in meteorites with > 16% Ni cannot be attributed to high pressures, but to supercooling or an unusually fast cooling rate
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The isotopic composition of krypton in meteorites
Journal of Geophysical Research, 1964The isotopic composition and amounts of krypton extracted from four stone meteorites and one sample of meteoritic troilite have been measured. For the two chondrites Bruderheim and Abee, and the troilite phase of Canyon Diablo, the isotopic composition of krypton was found to be different from the isotopic composition of krypton in the atmosphere.
W. B. Clarke, H. G. Thode
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