Mars Global Surveyor
Mars Orbiter Camera

Defrosting Gully Aprons

MGS MOC Release No. MOC2-398, 21 June 2003


NASA/JPL/Malin Space Science Systems

This is a late winter Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture of frost-covered gullies in a crater in the martian southern hemisphere. The dark spots are areas where the frost has begun to change or sublime away. The gullies are formed by a combination of mass movement (landsliding) and possibly fluid flow through the channels--whether the fluid was liquid water or some other material is unknown. Today, the surfaces are dry and subjected to the seasonal coming-and-going of carbon dioxide frost. The image is located near 71.0°S, 95.5°W. Sunlight illuminates the scene from the upper left.


Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, California. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, California and Denver, Colorado.

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