This image from the Mars Reconnaissance Orbiter shows twisting dark trails criss-crossing light-colored terrain on the surface of Mars. The dark trails were formed by miniature wind vortices, known on Earth as dust devils or whirlwinds. They are formed by rising columns of warm air and typically only last a few minutes. As these dust devils roll across the surface of Mars, they remove the light colored dust to reveal the darker colored material beneath.
NASA, HiRISE, MRO, LPL (U. Arizona)