This movie clip shows several gusts and whirlwinds carrying dust as they move toward NASA's Mars Exploration Rover Spirit. It consists of frames taken by the navigation camera on Spirit during the afternoon of the rover's 501st martian day, or sol (May 31, 2005). The camera was facing into the wind. Contrast has been enhanced for anything in the images that changes from frame to frame, that is, for the dust moved by wind.