Martian north polar terrain. Coloured satellite image ofice-covered sand dunes in the north polar region of Mars. Wind action has created crescent-sha

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Martian north polar terrain. Coloured satellite image ofice-covered sand dunes in the north polar region of Mars. Wind action has created crescent-shaped dunes (right half of image). The dark circular patches on the left are areas where frozen carbon dioxide has sublimated (turned from solid direct to gas) to reveal the darker basaltic sand underneath. Image obtained by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter (MRO) on 9th February 2008. The width of this image is roughly kilometres across.

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Size: 4048px × 5257px
Photo credit: © NASA/JPL/UNIVERSITY OF ARIZONA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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