NASA's HiRISE has sent back a rather peculiar image of a circular landform on the surface of Mars.
The feature, which measures nearly 1.2 miles (2 km) wide, looks like some kind of circular island surrounded by a "sea" of smooth looking lava flows. It's located in the Athabasca region of Mars, which contains some of the youngest lava flows on the planet.
NASA scientists suspect that volcanism played a part in creating this strange feature:
Perhaps lava has intruded underneath this mound and pushed it up from beneath. It looks as if material is missing from the mound, so it is also possible that there was a significant amount of ice in the mound that was driven out by the heat of the lava. There are an array of features like this in the region that continue to puzzle scientists.
NASA is hoping to get some more images of the object and others around it to learn more.
Image credit: NASA/JPL-Caltech/University of Arizona.