At some moment between May of 2003 and September of 2007 a cluster of meteorites struck the Martian sands, excavating craters and blasting the rusty dust away to reveal the dark underlying surface layers. Most likely the result of one object that broke up in the thin atmosphere of Mars, its pieces landing near each other, the two largest craters seem to have formed at exactly the same time, the resulting compression waves working together to blast dust away in a dividing line between them.

The area shown here is approximately 700 feet wide.

These multiple impact craters are common on Mars, and they would be on Earth as well except that the pieces usually break up and disintegrate in our thicker atmosphere before reaching the surface.

This image was taken by the HiRISE camera aboard the Mars Reconnaissance Orbiter on January 17, 2009.

Image credit: NASA/JPL/University of Arizona