Sand dunes often accumulate in the floors of craters. In this region of Lyot Crater, NASA’s Mars Reconnaissance Orbiter (MRO) shows a field of classic barchan dunes on Jan. 24, 2018.
Just to the south of the group of barchan dunes is one large dune with a more complex structure. This particular dune, appearing like turquoise blue in enhanced color, is made of finer material and/or has a different composition than the surrounding.
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington.
Image Credit: NASA/JPL-Caltech/Univ. of Arizon