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Monday, November 23, 2009 |
Monday, November 23, 2009 |
Photo: Riddle of Mars's Mysterious "Spiders," "Fans" SolvedThe spiders are delicate tunnels under the polar ice generated by melting carbon dioxide gas, while the fans are alternating deposits of carbon dioxide "snow" (white) and dust (black) thrown out by the erupting gas, experts say. Images courtesy NASA/JPL/University of Arizona
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