meteoritics
enUKme·te·or·it·ics
M0251250 (mē′tē-ə-rĭt′ĭks)meteoritics
(ˌmiːtɪəˈrɪtɪks)me•te•or•it•ics
(ˌmi ti əˈrɪt ɪks)n. (used with a sing. v.)
| 单词 | meteoritics |
| 释义 | meteoriticsenUKme·te·or·it·icsM0251250 (mē′tē-ə-rĭt′ĭks)meteoritics(ˌmiːtɪəˈrɪtɪks)me•te•or•it•ics(ˌmi ti əˈrɪt ɪks)n. (used with a sing. v.) meteoriticsMeteoriticsenUKMeteoriticsa branch of science that studies meteoric material in all its states and manifestations, including meteorites and their falls to the earth. The term “meteoritics,” now accepted in all countries, was proposed in 1889 by the Russian scientist lu. I. Simashko. Meteoritics primarily deals with the study of the motions of meteoroids in interplanetary space and in the earth’s atmosphere, interactions of meteoroids with the atmosphere, and the circumstances surrounding the falls of meteorites to the earth. In addition, it studies the chemical and mineral compositions, structure, and physical properties of meteorites, as well as regularities in both the composition and structure of meteorites. Meteoritics is also concerned with the study of radioactivity and isotopic composition of individual elements in meteorites, the study of traces of the action of high-energy cosmic particles in meteorites, and the determination of the age of meteorites. All the fields of study given above are directed at solving the fundamental problem of meteoritics—the origin of meteorites. In addition to its own specific methods, meteoritics also uses methods borrowed from other sciences, such as astronomy, physics, chemistry, mineralogy, geophysics, geochemistry, and metallurgy. Meteoritics originated at the end of the 18th century, when E. Chladni, after studying the Pallasovo Zhelezo meteorite that fell in Siberia in 1749, first proved the cosmic origin of that meteorite and advanced a hypothesis on the origin of meteorites that considered them to be fragments of larger bodies. By the 1970’s meteoritics had been extensively developed. Czechoslovakia, the USA, the Federal Republic of Germany, and Canada have set up networks for automatically observing meteors (bolides) using cameras; such a network has also been set up in the USSR. Various highly sensitive methods for studying meteorites have been developed, the ages of various meteorites have been determined, several dozen new minerals have been discovered, and important data on the primary material of the solar system have been obtained. In the USSR research in meteoritics is directed by the Committee on Meteorites of the Academy of Sciences of the USSR. The results of research are published in the collections Meteoritika. REFERENCESKrinov, E. L. Osnovy meteoritiki. Moscow, 1955.Mason, B. Meteority. Moscow, 1965. (Translated from English.) E. L. KRINOV |
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