During an August 20 event at NASA headquarters, called Ancient Earth, Alien Earths, a panel of scientists from NASA and other organizations discussed how vastly different and inhospitable we all would find ancient Earth, if we could go back in time. Despite the conditions, though, it was an environment in which life began and evolved – and understanding how that was possible could help us recognize habitable planets around other stars.
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Ancient Earth, Alien Earths
