拍品专文
This is a smaller oriented meteorite from the Chelyabink meteorite shower—and as is the case with the previous lot, less than 1% of all meteorites exhibit this degree of orientation. As a result of the damage created by Chelyabinsk, scientists are racing to come up with a comprehensive global strategy to protect Earth from a larger bombardment. About 13,000 Near-Earth Objects (NEOs) like the Chelyabinsk parent body have been discovered to date; nearly 900 of them are a kilometer in diameter or larger. More than 1600 of these bodies have been officially classified as “Potentially Hazardous Asteroids.” Chelyabinsk is a member of the least-common ordinary-chondrite group—the LL chondrites. It wandered through interplanetary space for a scant 1 million years, which suggests that Chelyabinsk was derived from the recent disruption of a small Earth-crossing asteroid that was itself broken off the main LL parent asteroid in the more-distant past. During one or more of these collisional events, Chelyabinsk was significantly shocked; pools of impact melt have been documented in numerous specimens.