Exhumed Crater

After the Odyssey spacecraft had completed a full Mars year of observations of the red planet Image of the Day looked back over this first mars year. Focus was on four themes: 1) the poles - with the seasonal changes seen in the retreat and expansion of the caps; 2) craters - with a variety of morphologies relating to impact materials and later alteration, both infilling and exhumation; 3) channels - the clues to liquid surface flow; and 4) volcanic flow features. While some images have helped answer questions about the history of Mars, many have raised new questions that are still being investigated as Odyssey continues collecting data as it orbits Mars.
This daytime VIS image was collected on December 12, 2002 during the northern summer season. The crater at the upper right was once buried and is now being exhumed. This region has several different layers of material, each layer with a different surface texture. The lower layer, which includes the crater, was eroded and then buried at some time in the past. Now the upper layer that covered the crater is being removed and the crater is in view again. Loose material in the region is collecting in depressions and forming small dunes.