In Western Olympia Undae, a region along the high polar latitudes of Mars, young windblown systems are emerging beneath the cliffs of the North Polar layered deposit. Persistent downslope winds, coupled with an ample supply of sand, create ideal conditions for the development of new bedforms near their sand source.

These nascent features, ranging from centimeters to meters in height, are known as “protodunes.” As the term suggests, these transient landforms often evolve into fully formed sand dunes with steep avalanche slopes, referred to as “slipfaces,” which provide clues about migration direction. Protodunes here gain sand volume, develop slipfaces, and transition into fully formed barchan dunes several meters tall within 3 to 5 annual cycles.

This view shows two such protodunes upwind of the single taller dune (on the right). This knowledge is thanks to repeat targeting by MRO HiRISE, our digital terrain models and a recent publication that highlights some of these rapid changes.

Written by: Matthew Chojnacki  (7 February 2018)