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> Mars: Dunes in Abalos Undae

Mars: Dunes in Abalos Undae

author: NASA/JPL/Univ. of Arizona/Novapix

reference: a-mar11-00035

Image Size 300 DPI: 21 * 16 cm

This enhanced-color close-up (1.2 kilometer across, 0.75 miles) shows an example of dunes in Abalos Undae. The Abalos Undae dune field stretches westward, away from a portion (Abalos Colles) of the ice-rich north polar layered deposits that is separated from the main Planum Boreum dome by two large chasms. These dunes are special because their sands may have been derived from erosion of the Rupes Tenuis unit (the lowest stratigraphic unit in Planum Boreum, beneath the icier layers) during formation of the chasms. Some researches have argued that these chasms were formed partially by melting of the polar ice. The enhanced color data illuminate differences in composition. The dunes appear blueish because of their basaltic composition, while the reddish-white areas are probably covered in dust. Upon close inspection, tiny ripples and grooves are visible on the surface of the dunes; these features are formed by wind action, as are the dunes themselves. This false-color image from the HIRISE (High Resolution Imaging Science Experiment) camera on Mars Reconnaissance Orbiter was taken on september 30, 2008.

Keywords for this photo:

2008 - ASTRONOMY - DUNE - FALSE COLOR - GEOLOGY - HIRISE - MARS - MARS RECONNAISSANCE ORBITER - MRO - NORTH POLE - PLANET - POLE -