This image from NASA's Mars Reconnaissance Orbiter shows two new craters on Mars with the same distinctive pattern of relatively blue ejecta surrounded by a dark blast zone and arcing patterns. This pattern indicates an oblique impact angle with a bolide.
This image from NASA's Mars Reconnaissance Orbiter shows barchan sand dunes, common on Mars often forming vast dune fields within very large (tens to hundreds of km) impact basins. The regions upwind of barchans are usually devoid of sandy bedforms.
This enhanced color image from NASA's Mars Reconnaissance Orbiter (MRO) shows the heavily channeled and ancient southern highlands of Mars. The elongated and jagged features are windblown dunes, perhaps hardened and eroded.
NASA's Mars Reconnaissance Orbiter shows bright ripples line the topography in this region, formed within a past climate. Dark dunes and sand streaks, composed of basaltic sand, have moved and filled lower areas, pushed by more recent winds.
This image from NASA's Mars Reconnaissance Orbiter shows a roundish crater with three channels breaching the rim and extending to the south. The crater has been filled by sediments and may have been an ancient lake.