Barchan sand dunes on Mars

This image from HiRISE, on the Mars Reconnaissance Orbiter, shows two flat top mesas in southern Mars when the season was changing from Spring to Summer.  Images Credit: HiRISE, MRO, LPL (U. Arizona), NASA

The dunes have a morphology indicating formative winds blowing from east to west (from right to left).

Barchan sand dunes on Mars

The dark arc-shaped droplets of fine sand are called barchans, and are the interplanetary cousins of similar Earth-based sand forms.

Barchans can move intact a downwind and can even appear to pass through each other.

Barchan sand dunes on Mars

Barchan dune explained

Image from the Wikimedia Commons

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