The Russell Crater dune field is covered seasonally by carbon dioxide frost, and this image shows the dune field after the frost has sublimated (evaporated directly from solid to gas). There are just a few patches left of the bright seasonal frost.

Numerous dark dust devil tracks can be seen meandering across the dunes. The face of the largest dune is lined with gullies. The source of the gullies is unclear but could involve erosion by the seasonal carbon dioxide ice.
Written by: Candy Hansen

All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible: Image: NASA/JPL/University of Arizona

For information about NASA and agency programs on the Web, visit: http://www.nasa.gov. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems is the prime contractor for the project and built the spacecraft. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona. The image data were processed using the U.S. Geological Survey’s ISIS3 software.