24 July 2006
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies on the wall of a martian south mid-latitude impact crater. The channels in each gully head beneath an eroding overhang of layered rock, providing support for the hypothesis that some -- if not all -- martian gullies result from release of groundwater to the surface.
Location near: 33.0°S, 213.4°W
Image width: ~3 km (~1.9 mi)
Illumination from: upper left
Season: Southern Autumn