Lunar meteorite - a meteorite , originally originated on the moon . As a rule, lunar meteorites are classified as the result of short-term lunar phenomena . It has been suggested that tectites may be attributed to lunar meteorites, but this point of view is not shared by the scientific community [2] .
Content
Discovery of lunar meteorites
In January 1982, American geologist John Schutt during the expedition to Antarctica under the ANSMET program, he discovered a meteorite with unusual characteristics. This meteorite, which later received the name Allan Hills 81005 , was sent to Washington , where the geochemist of the Smithsonian Institution Brian Mason concluded that this sample differs in its properties from all known meteorites and rather resembles the characteristics of lunar rocks brought to Earth during the Apollo program [3] . A few years later, Japanese scientists recognized the object called Yamato 791197 as a lunar meteorite discovered in 1979 in Antarctica. As of October 2010, 134 lunar meteorites with a total mass of more than 46 kg have been identified. All lunar meteorites were found in desert areas - in Antarctica , North Africa and in the Sultanate of Oman . In Europe, North America and South America, no lunar meteorite has yet been found [4] .
The determination of the lunar origin of a meteorite is made by comparing its chemical and isotopic composition with samples of lunar soil brought from the moon during the Apollo program.
Earth Hit
According to meteoritic estimates, most lunar meteorites form in lunar craters that are several kilometers in diameter or less [5] . To date, no lunar crater has been unequivocally identified as a source of lunar meteorites, although there is an assumption that the meteorite Sheikh el-Ucheymir 169 may originate from the Lalande crater on the visible side of the moon [6] [7] .
Measurements of the concentration of noble gases showed that all lunar meteorites were ejected from the lunar surface during the last 20 million years, and most of them - in the last 100 thousand years. After leaving the surface of the moon, most lunar meteorites found themselves in earth orbit and eventually fell to the surface of the earth . Part of the meteorites ejected from the lunar surface turns out to be in solar orbits and may subsequently cross the Earth's orbit [8] .
Scientific Importance
All samples of lunar rocks, delivered as a result of six missions of the Apollo spacecraft, were collected in the central part of the visible side of the moon, which, as the Lunar Prospector program later showed, is characterized by the presence of geochemical anomalies. In contrast to these samples, lunar meteorites are of random origin and, therefore, provide a more representative sampling of the properties of the lunar surface than those of the Apollo project. It is estimated that half of the lunar meteorites are likely to be samples of the rocks of the far side of the moon .
After the discovery in 1982 of the first lunar meteorite in the scientific community, it was suggested that some earlier meteorites with unusual characteristics may have a Martian origin . Confirmation of the origin of lunar meteorites speaks in favor of the hypothesis that the impact on the surface of Mars can also lead to the emergence of meteorites hit the Earth. By analogy, there are also assumptions about the possibility of the appearance of "Earth meteorites" on the surface of the moon [9] . The search for “terrestrial meteorites” on the moon is of great interest to geologists, since there is a hypothetical probability of detecting terrestrial rocks older than 3.9 billion years old, which collapsed on Earth due to various geological processes , but could persist on the moon.
Private property
Since all lunar soil samples collected during the Apollo program are owned by the US government (and, similarly, lunar soil samples delivered to Earth by Soviet automatic stations Luna-16 , Luna-20 and Luna-24 are property of the USSR government ( then - the Russian Federation )), the only way to obtain lunar soil into private ownership is to assign or purchase lunar meteorites. It is known that three tiny samples of lunar soil were sold at auction for $ 442,500 in 1993 [10] [11] [12] .
See also
- Martian meteorite
Notes
- ↑ NWA 5000 meteorite
- ↑ Appearance of tektites on the Earth, “Nature” ı 4, 1998 E.V. Dmitriev
- ↑ Marvin, UB The first lunar meteorite (Eng.) // Geophys. Res. Lett. : journal. - 1983. - Vol. 10 , no. 9 - P. 775-778 . - DOI : 10.1029 / GL010i009p00775 . - .
- ↑ Washington University in St. Louis: How to Rock From the Moon?
- ↑ James N. Head, H. Jay Melosh, and Boris A. Ivanov; JN; Melosh, HJ; Ivanov, BA High-speed ejecta from small craters (eng.) // Science. - 2002. - Vol. 298 , no. 5599 . - P. 1752-1756 . - DOI : 10.1126 / science.1077483 . - . - PMID 12424385 .
- ↑ Gnos, E .; Hofmann, BA; Al-Kathiri, A .; Lorenzetti, S .; Eugster, O .; Whitehouse, MJ; Villa, I .; Jull, AJT; Eikenberg, J.; and others; Krähenbühl, Urs; Franchi, Ian A .; Greenwood, Richard C. et al. Pinpointing for the evolution of the moon ( Science ) // Science: journal. - 2004. - Vol. 305 , no. 5684 . - p . 657-659 . - DOI : 10.1126 / science.1099397 . - . - PMID 15286369 .
- Je Je Je ff ff New New не не не не не не не . Planetary Science Research Discoveries (October 31, 2004).
- ↑ B. Gladman and J. Burns, “The Delivery of Martian and Lunar Meteorites to Earth.” Bulletin of the American Astronomical Society 28 (1996) 1054.
- ↑ John Armstrong, Llyd Wells, and Guillermo Gonzalez; J; Wells, Llyd E .; Gonzalez, Guillermo. Rummaging through Earth's Attic for Remains of Ancient Life (Eng.) // Icarus : journal. - Elsevier , 2002. - Vol. 160 - P. 183-196 . - DOI : 10.1006 / icar.2002.6957 . - . - arXiv : astro-ph / 0207316 .
- ↑ NY Times story, FBI Revisits Earthly Theft of Moon Rock .
- Ro Ro Ro A A: A Personal Account . Geotimes Magazine, Joseph Gutheinz, November 2004.
- ↑ "Hunting Moon Rocks" . Alvin Sun Advertise, Judy Zavalla, 4 November 2009.