NASA/JPL/Malin Space Science Systems
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the walls and floor of a wide trough in the Sirenum Fossae region near 26.4°S, 140.7°W. Boulders rolled down the trough walls as they eroded out of the rock outcrops exposed on the upper slopes. Sunlight illuminates this scene from the upper left; the image covers an area 3 km (1.9 mi) wide.
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.