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Article: Life on Earth may have first emerged 4.4 billion years ago: study
- Article from:
- Xinhua News Agency
- Article date:
- May 21, 2009
CopyrightCopyright 2009 Xinhua News Agency. Provided by ProQuest LLC. (Hide copyright information)
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Life on Earth may have first emerged 4.4 billion years ago: study
LONDON, May 21 (Xinhua) -- Life on Earth may have begun about
4.4 billion years ago, several hundred million years earlier than
previously thought, researchers who had studied asteroid
bombardments, reported on Thursday.
Our planet formed 4.6 billion years ago, and many scientists
believe it was sterilized by numerous asteroid impacts during the so-
called Hadean Eon, 4.5 billion to 3.8 billion years ago,
particularly through a cataclysmic event known as the Late Heavy
Bombardment about 3.9 million years ago, making it impossible for
life to survive.
But Oleg Abramov and Stephen Mojzsis of the University of
Colorado at ...