Monday, April 28, 2008

Snowball Earth

Could the Earth once, over 600 million years ago, have been completely covered by ice? Convention tells us that there should always be some parts of the Earth that are ice-free even in the worst of ice ages. But geological evidence tells us that even the equator was at that time covered by glaciers.



Part 2 | Part 3 | Part 4 | Part 5 || from 2001

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