How is it possible that Mars can have dust devils and global dust storms with such a thin atmosphere?
Jon Wallen, Renton, Washington
Published: Monday, August 29, 2011
Mars requires a wind speed about 10 times faster than on Earth to lift dust. Once the dust is off the surface, it needs to remain suspended in the air to form a cloud. Because Mars is less massive and thus has a lower surface gravity than Earth, dust falls to the surface more slowly.