Apr 1 2016
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For forty years, astronomers have puzzled over the miles-high mounds rising from of the centers of Martian craters.…
Oct 30 2015
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Turgai, Kazakhstan might not look like much besides wide, sweeping plains. But over the past few years,…
Oct 31 2010
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Silbury Hill is a huge artificial mound in southern England, about 130 feet high and covering five acres. Europe's…