This image, taken by the Mars orbiter camera on NASA’s Mars Global Surveyor spacecraft, shows gullies on martian crater walls that may be carved by liquid water melting from remnant snow packs. Numerous gullies are seen, with a remnant of the snow pack (arrow) proposed to be the source of water that eroded the gullies. This Mars orbiter camera image (number M09-2875) covers an area of 2.8 km (1.7 miles) by 4.5 km (2.8 miles) and is located at 33.3 degrees south, 92.9 degrees east. North is toward the top, and illumination is from the left. Image 1
Image Credit: NASA/JPL/MSSS/Phil Christensen
Image 2
Image Credit: NASA/JPL/MSSS/Phil Christensen		 This image, taken by the Mars orbiter camera on NASA’s Mars Global Surveyor spacecraft, shows the details of remnant snowpacks found in protected hollows on the cold, pole-facing slopes in Dao Valles. This Mars orbiter camera image (number M03-04950) covers an area of 2.8 km (1.7 miles) by 5 km (3.1 miles) and is located at 35.7 degrees south, 90.9 degrees east. North is toward the top, and illumination is from the left.
This visible-light image, taken by the thermal emission imaging system on NASA’s 2001 Mars Odyssey spacecraft, indicates that gullies on martian crater walls may be carved by liquid water melting from remnant snow packs. The gullies in the top right-center appear to emerge from beneath and within a gradually disappearing blanket of snow. The current snow pack in this crater (located at 43 degrees south, 214 degrees east) appears to remain only on the cold, pole facing cater wall (top). On the less-shaded, warmer sides of the crater (left), the snow cover has completely disappeared, leaving the gullies exposed. The image shows an area 12.6 km (7.8 miles) by 10.3 km (6,4 miles). North is toward the top, and illumination is from the left. Image 4
Image Credit: NASA/JPL/ASU
Image 4
Image Credit: NASA/JPL/ASU		 This visible-light image, taken by the thermal emission imaging system on NASA’s 2001 Mars Odyssey spacecraft, indicates that gullies on martian crater walls may be carved by liquid water melting from remnant snow packs. The gullies in the top right-center appear to emerge from beneath and within a gradually disappearing blanket of snow. The current snow pack in this crater (located at 43 degrees south, 214 degrees east) appears to remain only on the cold, pole facing cater wall (top). On the less-shaded, warmer sides of the crater (left), the snow cover has completely disappeared, leaving the gullies exposed. The image shows an area 14.8 km (9.2 miles) by 21.6 km (13.4 miles). North is toward the top, and illumination is from the left.
This large (49MB) Quicktime movie is a recreation illustrating a proposed model of Martian snowfall and meltoff creating gullies. Movie Still