The shifting sands of Mars.
The rover was investigating the whirlwinds on Mount Sharp's sand dunes to check how far the winds move the grains of sand.
NASA's Curiosity Mars Rover recently spotted several dust devils swirling around parts of the planet.
The pictures support a theory that wind is shaping the landscape on Mars.
The first image was taken on January 23, 2017, during the 1,587th Martian day, or sol, of Curiosity's work on Mars. The area of ground shown in the images spans about 3 feet (about 1 meter) left-to-right. Those tracks go from clearly defined to blurry as the image shifts.
When Curiosity landed inside Gale Crater in August 2012, MARDI recorded the descent from the rover's point of view. Since then, it has driven almost 10 miles (16 kilometers).
The images were taken in pairs about 12 seconds apart, with about 90 seconds in between each pair.