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People have been finding Moon rocks and Mars rocks at the South Pole．Why the South Pole? It seems that the South Pole (Antarctica) is a really good place to look for them and to find them．
Part of the reason for this is that Antarctica is a very large slab of ice sitting on a bed of rock. The ice doesn't stay still．It moves，ever so slowly，from the centre of Antarctica down to the coast (海岸)．
When meteorites (陨石) fall on the Antarctic ice，some stay on the surface but most get trapped a few metres down．After all，they do come down with some force and heat!
The meteorites get caught up in the ice as they move to the sea and a few million years later most of them reach the coastine．
On the way to the sea some of the ice passes round mountain ranges where the meteorites get dislodged．In other words，the ice presses them to the surface．
Anywhere else on the earth the meteorites either land in the ocean or cover themselves underground in the soil，never to be seen again．
In Antarctica，the little black rocks show up very nicely against the white background.
People who live where there are trees and where there is a completely different climate aren't so lucky! | 