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TODAY’S THEMIS IMAGE: Tithonium Chasma, in Valles Marineris:

This image covers part of Tithonium Chasma, which is part of the Valles Marineris system of canyons that stretch for thousands of kilometers. The contrast between dark sandy surfaces covered by dunes and bright dusty surfaces with a rather uniform appearance is clearly visible in the bottom half of the image. Small cut channels and flat-topped buttes, representing an erosional remnant of a resistant layer of rock, are also observed and covered by dust. In the top half of the image, ridgelines are observed in the canyon walls with small dark streaks trailing downslope; these streaks suggest that the sediments covering this area occasionally become unstable and slide.