Are Martian dust devils different than the ones on Earth?
KE: The Martian surface is much more dusty than the surface of the Earth because Earth has rain to wash away most of the dust that settles out of the sky. But Mars doesn’t. What’s neat about the Martian dust devils is that as they move they create a kind of art. All that extra dust on the ground means that the dust devils leave tracks behind them where they have either picked up dust or disturbed the dust lying about on the surface. Most of the time these tracks are darker than their surroundings, but sometimes they are lighter it just depends upon whether the surface under the thin coating of dust is lighter or darker than the dust itself. In some places on Mars, you can get hundreds of crisscrossing dust devil tracks. They make a pattern that some say resembles Jackson Pollack paintings. Others say the patterns resemble something their 2-year-old might do with crayons. Q: How do you detect dust devils in the Global Surveyor data? KE: NASA’s Mars Global Surveyor spacecraft has three c
