NASA/JPL/Malin Space Science Systems
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle image shows Hecates Tholus, the northernmost of the three large Elysium volcanoes. The non-circular pit just southwest (toward lower left) of the center of this view is the summit caldera, a complex depression formed by collapse. This volcano has several large impact craters on its surface, indicating that it is a relatively old landform. None of the martian volcanoes are thought to be active today, and none of the MOC images of the martian volcanoes obtained thus far give any indication to the contrary. Hecates Tholus is located at 32°N, 210°W. This picture is illuminated by sunlight from the lower left and covers an area about 170 km (~105 mi) across.
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.