NASA’s Mars Curiosity Rover has hit paydirt, discovering rock formations on the Red Planet that [were] most likely formed by the vigorous flow of a stream of water in Mars’ ancient history, NASA announced Thursday.And somewhere, the shade of the late Carl Sagan is nodding and muttering, "Told you so!"
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Water is only one of three items required for life to have ever existed on Mars. The other two are a source of carbon (for organic compounds) and an energy source. All must have been present simultaneously for life to have existed. None individually is evidence of earlier (or current) life on Mars. Even organic compounds, while suggestive of life, can be formed in space in a number of other ways. So we still have a lot of research yet to do.
There be cool pictures at the links above!