Scientists from NAI's New York Center for Astrobiology at Rensselaer Polytechnic Institute have used the oldest minerals on Earth to reconstruct the atmospheric conditions present on Earth very soon after its birth. The findings, which appear in the December 1, 2011 issue of Nature, are the first direct evidence of what the ancient atmosphere of the planet was like soon after its formation and directly challenge years of research on the type of atmosphere out of which life arose on the planet.
The scientists show that the atmosphere of Earth just 500 million years after its creation was not a methane-filled wasteland as previously proposed, but instead was much closer to the conditions of our current atmosphere. The findings, in a paper titled "The oxidation state of Hadean magmas and implications for early Earth's atmosphere," have implications for our understanding of how and when life began on this planet and could begin elsewhere in the universe.
For more information: http://astrobiology.nasa.gov/articles/earth-s-early-atmosphere-an-update/
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