This IR image shows part of the dune field on the floor of Rabe Crater. The dunes are "brighter" than the surrounding material, indicating that they are warmer. In visible wavelength images the dunes are dark, because they are comprised of basaltic sand.
Orbit Number: 51694 Latitude: -41.6772 Longitude: 34.5902 Instrument: IR Captured: 2013-08-09 10:00
Image credit: NASA/JPL-Caltech/Arizona State University