The Antarctic search for meteorites

Tuesday, November 23, 1999

The richest collecting ground for meteorites on Earth is the Antarctic plateau. In most other parts of the world meteorites are camouflaged by other rocks and easily broken down by rain and temperature changes.

Meteorites landing on Antarctic ice sink into the snow and are preserved unchanged for thousands and even millions of years. They are transported slowly by the moving ice sheets to blue ice fields. Blue ice fields are areas where the ice is forced upwards by mountains under, or rising above the ice. Ice is gradually blown away by strong winds leaving meteorites concentrated and ready for gathering.

The US-funded Antarctic Search for Meteorites (ANSMET) has spent 22 seasons collecting in Antarctica. The program is run by Ralph Harvey from Case Western Reserve University, Cleveland, Ohio. During that time more than 8 000 meteorites have been found. When you add meteorites found by people associated with Japanese and European programs the total is around 16 000. Some of these finds may be fragments of the same rocks, even so, that is more meteorites found in 20 years than have been found in the rest of the world in the past two centuries.