Ius Chasma dunes: they move

Many dunes on Mars are actively migrating, like these dunes (view is 0.4×0.5 km, 0.25×0.31 mi). These are found deep in Ius Chasma, one of the Valles Marineris. These dunes slowly migrate toward the right, pushed by winds blowing from the lower and upper left.

Comparing this recent image with the first HiRISE image taken ~10.5 years ago (that’s ~4.4 Mars years) shows development of a crest linking these two dunes, indicating the wind from the upper left has been most active over the last few years. Click on the grayscale image to the left to see an animation of this change. If you want to learn more about Valles Marineris dunes, you can read about them in this paper by Chojnacki et al. (2014). (HiRISE ESP_053595_1725, NASA/JPL/Univ. of Arizona)