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View Full Version : Solving the Puzzle of Mars' Spiral Icecaps



Fraser
2005-Sep-07, 10:28 AM
SUMMARY: The spiral shape of the Martian icecaps has puzzled astronomers since they were discovered. No place on Earth, or in the rest of the solar system has this structure. But what causes them? The icecaps are illuminated by the Sun at a low angle, so the light only hits one side of crevices. Some of the ice turns directly to water vapour and floats across the crevice; it refreezes on the part of the crevice in shadow. This slowly moves ice around on the icecap. A researcher from the University of Arizona has created a simulation which matches the observed structure of the Martian icecaps, including the irregularities.

View full article (http://www.universetoday.com/am/publish/puzzle_mars_spiral_icecaps.html)
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