This image, captured by the HiRISE camera on the Mars Reconnaissance Orbiter (MRO), reveals a roughly 32-foot (10-meter) wide sinkhole on the surface of Mars. The hole is located in a region called Arsia Mons, which is a shield volcano in the Tharsis volcanic province.

Several such holes have been observed in the Tharsis region, and they are believed to be formed by the collapse of underground caverns created by lava flows. As the lava empties out, the roof of the cavern can become unsupported and collapse, creating the sinkholes. The presence of these sinkholes suggests that the volcanic activity in the Tharsis region was once much more extensive than it is today.