This observation shows dark sand dunes marching over the ridges created by an alluvial (water-deposited) fan in an impact crater.

These dunes may be active today, but we haven’t yet observed them at significantly different times to measure the movement. The dunes are moving from northwest (upper left) to southeast, with the steep slope facing downwind.

Be sure to check out this stereo anaglyph of the scene. (This cutout is at full resolution.)

ID: ESP_025625_1580
date: 14 January 2012
altitude: 257 km

https://uahirise.org/hipod/ESP_025625_1580
NASA/JPL-Caltech/UArizona
#Mars #science #NASA