NASA's Mars Global Surveyor shows gullies formed in the walls of an impact crater on Mars. Such gullies might result from seepage and runoff of groundwater.

5 December 2005
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies formed in the walls of an impact crater. Such gullies might result from seepage and runoff of groundwater; others have suggested snowmelt might be involved, although there is no evidence for snow at this location.

Location near: 35.7°S, 207.6°W
Image width: width: ~3 km (~1.9 mi)
Illumination from: upper left
Season: Southern Summer

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