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This Mars Odyssey spacecraft THEMIS (Thermal Imaging System) image released 27 March, 2002 by NASA shows a sinuous valley network channel with sharp bends cutting across the cratered highlands of the southern hemisphere of Mars. The channel is named Nirgal Vallis, which is from the Babylonian word for "Mars". Nirgal Vallis is a channel with a total length of approximately 500 km. It is approximately 6 km wide in this region. Gullies and alluvial deposits discovered by Mars Global Surveyor are clearly visible on the polar-facing (south) wall and floor of Nirgal Vallis. These gullies appear to emanate from a specific layer in the walls. There is a pronounced sparsity of gullies on the equator-ward facing slopes. The gullies have been proposed to have formed by the subsurface release of water. (KEYSTONE/EPA PHOTO/NASA) === ===