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ANSMET
ANSMET (Antarctic Search for Meteorites) is a program funded by the Office of Polar Programs of the National Science Foundation that looks for meteorites in the Transantarctic Mountains. This geographical area serves as a collection point for meteorites that have originally fallen on the extensive high-altitude ice fields throughout Antarctica. Such meteorites are quickly covered by subsequent snowfall and begin a centuries-long journey traveling "downhill" across the Antarctic continent while embedded in a vast sheet of flowing ice. Portions of such flowing ice can be halted by natural barriers such as the Transantarctic Mountains. Subsequent wind erosion of the motionless ice brings trapped meteorites back to the surface once more where they may be collected. This process concentrates meteorites in a few specific areas to much higher concentrations than they are normally found everywhere else. The contrast of the dark meteorites against the white snow, and lack of terrestrial rocks on the ice, makes such meteorites relatively easy to find. However, the vast majority of such ice-embedded meteorites eventually slide undiscovered into the ocean.
== Importance ==
The ANSMET program, together with parallel Antarctic collection programs run by Japan, China, and other nations, is a major source of the extraterrestrial material that is available for scientific investigation. All of the material collected by ANSMET is curated for the purpose of research and public education, in contrast to meteorites collected privately, the bulk of which are frequently sold to collectors.
While the vast majority (>90%) of the meteorites found are ordinary chondrites, ANSMET has provided many rare meteorites, including many of the known lunar and martian meteorites such as ALH84001.〔(【引用サイトリンク】url=http://curator.jsc.nasa.gov/antmet/statistics.cfm )〕
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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