Images
Dunes on Ridges (3-D)

May 24, 2012
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.
Image source: https://hirise.lpl.arizona.edu/ESP_025625_1580
Credits
NASA/JPL-Caltech/University of Arizona