18 February 2004
Many craters and troughs at middle latitudes on Mars have gullies carved into their slopes. These gullies often have banked or even meandering channels that indicate a fluid with the properties of water may have been involved. Indeed, it is possible that such gullies indicate places where liquid water seeped out to the martian surface, or formed from melting ice, in the not-too-distant past. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example located in a crater in Terra Cimmeria near 37.7°S, 191.6°W. The picture was acquired only a few months ago in November 2003. Sunlight illuminates the scene from the left/upper left; the picture covers an area 3 km (1.9 mi) wide.