The Mars Color Imager (MARCI) camera on the Mars Reconnaissance Orbiter acquires daily global images of the planet and its weather patterns, which are then used to produce Mars weather reports. Movies made from the camera's images show Martian weather in motion (the numerous dark areas are the result of the spacecraft rolling to take images of the surface).
The circle at the bottom center of this image, which was taken in early November 2008, shows the location of the Spirit rover in Gusev Crater. To the south and west of this site are the white and rust-colored clouds of a dust storm that was under way at the time. MARCI co-investigator Bruce Cantor of MSSS noted the coming storm and alerted the rover team just in time for them to change their operation plan to conserve battery power. Had MARCI not provided the forecast, Spirit might have lost too much power during the storm, and the mission might have ended that week.