File:Crater Dunes (PIA25742 fig1).png

Context image

This VIS image shows a large sand sheet with surface dune forms as well as smaller sand dunes within an unnamed crater in Noachis Terra. These dunes are composed of basaltic sand that has collected in the bottom of the crater. The topographic depression of the crater forms a sand trap that prevents the sand from escaping. Dune fields are common in the bottoms of craters on Mars and appear as dark splotches that often lean up against the downwind walls of the craters. Dunes are useful for studying both the geology and meteorology of Mars. The sand forms by erosion of larger rocks, but it is unclear when and where this erosion took place on Mars or how such large volumes of sand could be formed. The dunes also indicate the local wind directions by their morphology.

Orbit Number: 92028 Latitude: -48.9171 Longitude: 34.0952 Instrument: VIS Captured: 2022-09-12 21:08

Please see the THEMIS Data Citation Note for details on crediting THEMIS images.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Science Mission Directorate, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.