Orson Welles Crater Dunes

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 five 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; 4) volcanic flow features; and 5) dunes. 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 November 13, 2003 during the southern summer season in Orson Welles Crater. Several landslides can be seen in this image. A sand sheet to the south of the landslides appears to be encroaching on the southernmost slide. This relationship indicates that the sand movement is likely actively occurring, and that the landslide was present prior to the sand moving up onto it.