Caught in the Act (Natural Colors; credits: NASA/JPL-Caltech/University of Arizona - Additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)

This image was targeted to study Knobs in Mars' Northern Plains (Vastitas Borealis), just North of Scandia Crater. What surprised scientists was the presence of a Dust Devil passing by.

As on Earth, Dust Devils form when ground heated by sunlight warms the air above it. The hot air rises, forming an updraft accompanied by vortical motions.
Because warm ground is a requirement, Dust Devils on Mars generally form in late Spring to Summer, especially at high Latitudes.

This image was taken in early Spring (2010), at a latitude of about 61° North. No Dust Devil has been seen this far from the Equator at such an early season before.