Why are so many meteorites found in Antarctica?
Antarctica's moving ice carries meteorites to certain blue-ice areas, where wind strips the surface away and leaves them stranded. Dark stones on white ice are easy to spot, and the cold, dry climate preserves them.
More than 40,000 meteorites have been recovered from Antarctica, a large share of all known meteorites. They didn't fall there more often than elsewhere; rather, Antarctica collects and displays them in a uniquely helpful way.
The secret is the ice sheet. Meteorites that land on the snow get buried and become part of the ice, which flows slowly outwards from the centre of the continent towards the coast, like a vast, slow river. Where this flow is blocked by mountains or buried ridges, the ice is pushed upwards. Strong, dry winds then wear the surface away by sublimation, ice turning straight into vapour, and by scouring. Over thousands of years this exposes old ice, recognisable by its blue colour, and the meteorites it contains are left stranded on the surface. These blue-ice fields act as natural concentration zones, gathering meteorites that fell over a huge area across very long periods of time.
Finding them is comparatively easy because a dark stone on blue or white ice stands out, and there are few local rocks to confuse things. The cold, dry environment also slows rusting, so some Antarctic meteorites have survived for hundreds of thousands of years or more.
Scientists realised this in 1969, when a Japanese team found nine meteorites close together near the Yamato Mountains. Since then, Japanese, American, European, Chinese and Korean programmes have searched the ice systematically. Antarctic finds include famous specimens such as ALH 84001 from Mars and the first meteorite recognised as coming from the Moon. Under the Antarctic Treaty system, collecting is carried out only by authorised scientific expeditions, and the specimens are curated for research.