HiRISE: Dome & barchan dunes in Newton Crater

This observation shows a small sand dune field on the floor of Newton Crater, an approximately 300 kilometer (130 mile) wide crater in the southern hemisphere of Mars. The image shows both dome and barchan dunes. Both these types of dunes are also found on Earth. Barchan dunes in particular are common on Earth, and are generally crescent-shaped with a steep slip face bordered by horns oriented in the downwind direction…. [More at link]