This large crescent dune in Kaiser Crater shows the scars of many types of seasonal erosional activities. Along its downwind slope are large gullies which are active during winter, when frost drives dune material downslope, carving out channels and creating fan-shaped aprons.

On the upwind slope (bottom), dust devil tracks are visible: dark lines and curlicues created during the spring season by small wind vortices vacuuming up a thin layer of dust and exposing the dark dune sand.

Note: Both the cutout and the above image are rotated so that North is to the right.

ID: ESP_020876_1330
date: 9 January 2011
altitude: 253 km

https://uahirise.org/hipod/ESP_020876_1330
NASA/JPL-Caltech/UArizona
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