MOSCOW, June 11 – RIA Novosti. Ukrainian and American geologists have analyzed the mineral and chemical composition of the grains, the Soviet scientists found near the site of the Tunguska meteorite, and came to the conclusion that they belonged to a class of meteorite carbonaceous chondrites, not a comet, as some researchers, reports Nature News.
Tunguska catastrophe took place over 100 years ago in the Stony Tunguska River basin, in the Evenki. The expedition, to get to the disaster area in 1927, found fallen timber on an area roughly equal to modern Moscow, but at the blast site was not found any signs of dropping, no wreckage of the cosmic body. According to most scientists, Tunguska body was a small comet, which is completely evaporated at high altitude.
group of geologists led by Victor Kvasnitsa Institute of Geochemistry, Mineralogy and Ore Formation NAS has provided convincing arguments in favor of the “meteorite” theory of the disaster, saying the discovery and mineralogical analysis “remains” of the heavenly bodies in a paper published in the journal Planetary and Space Science.
geologists studied microscopic grains were found a group of Soviet scientists in 1980, on the premises and one of the authors of the article – Nicholas Kovalyuh from the Institute of Environmental Geochemistry National Academy of Sciences of Ukraine. Imperfection techniques of that time did not allow explorers unambiguously confirm their meteoritic origin, which is why the discovery remained unknown to the world.
Kvasnitsa and colleagues filled the gap by examining the mineral composition of the grains by mass spectroscopy and scanning electron microscopy. It turned out that they are composed of graphite inclusions microdiamonds and “space” minerals – troilite, and taenita shreyberzita. According to geologists, this fact makes it possible to classify the Tunguska meteorite to a rare subtype of the number of carbonaceous chondrites, and calls into question the “comet” hypothesis of this cataclysm.
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