Rovers Document Dust Devils’ Trek Across Mars

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NASA’s Mars rover Spirit has caught a bevy of dust devils racing across the surface of the red planet , which researchers compiled into a stunning new movie.

While scaling Husband Hill at its Gusev Crater landing site, cameras aboard Spirit recorded several dust devils blowing across the martian surface. Dust devils form when localized heat and associated convection create dramatic small-scale vortices, which stir up dust and debris .

Researchers condensed the windy devils’ 12-minute, 17-second passing into a short black-and-white movie clip.

“Wind processes are the only active processes that we know are happening on Mars,” said Patrick Whelley, a rover science team member who has been studying the dust devil images, in a telephone interview. “They’re short term geologically … [but] they have shaped the landscape.”

Although NASA released the dust devil movie Aug. 19, Spirit actually photographed them July 13 during its 543rd day on Mars. The images have not been processed to enhance the contrast of the dust devils.

Spirit first observed dust devils on Mars near the beginning of the region’s spring season. While they increased in frequency as the season wore on, they dropped off for about two weeks during a dust storm, only to return in force once the storm had passed, NASA researchers said.

Whelley said images from Spirit and its robotic twin Opportunity show that dust devils perform an important role in contributing to the overall dust content in Mars’ atmosphere, and provide an additional tool for atmospheric modelers.

During early spring on Mars, dust devils typically wind their way from southwest to northeast across streaks that can be seen from orbit. As the season moves forward, the windy objects move from northwest to southeast in the same direction of the streaks, Mars researchers said, adding that scientists are still looking for the big dust devils that etched those streaks into the surface.

“My hope is to be able to take what we know now at Gusev and then apply it to the rest of the planet,” Whelley said.