When were meteorites first found in Antarctica?
The first was found in 1912 by an Australian expedition, but the discovery that the ice concentrates meteorites came in 1969 when Japanese scientists found nine near the Yamato Mountains.
The first find. In December 1912, members of the Australasian Antarctic Expedition, led by Douglas Mawson, found a stony meteorite on the snow in Adélie Land. It was named Adelie Land and is an L5 chondrite. A few more isolated finds followed over the next decades.
The breakthrough. In December 1969, a Japanese Antarctic research expedition team working near the Yamato Mountains found nine meteorites on an area of bare blue ice. Scientists realised that finding several different meteorites close together could not be chance. They suggested that the ice sheet concentrates meteorites.
How concentration works. Meteorites that fall on the ice sheet are buried and carried by the slowly flowing ice. Where ice meets mountains or buried ridges, it is pushed up, and strong dry winds remove ice by sublimation, exposing old blue ice and leaving the meteorites behind on the surface.
Expeditions. Japanese teams returned and found thousands more meteorites in the 1970s. In 1976, a joint American and Japanese team began searching, leading to the American ANSMET programme, which has collected more than 20,000 meteorites. Teams from China, Korea, Italy, Belgium and others have since joined.
Important finds. Antarctic meteorites include ALH 84001, the famous Martian meteorite; ALH A81005, the first recognised lunar meteorite; and EETA79001, which proved that some meteorites come from Mars.
Total. More than 45,000 meteorites have now been recovered from Antarctica, more than from any other region.