A dust devil recently caught in action on Mars was one hell of a storm. Stretching 20 kilometers up from the planet’s surface, the alien whirlwind would tower above its impish cousins on Earth.
“What’s interesting about this dust devil is it’s very, very tall,” says David Choi, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “To see one this size is very rare.”
NASA’s Mars Reconnaissance Orbiter took the lucky photograph using a high-resolution camera called HiRISE. On March 14, the camera spotted the dust devil leaving a trail across land in Mars’ northern hemisphere, where spring brings temperatures of up to -25° Celsius in some places.
Dust devils form on Mars the same way they do on Earth: Sunlight bakes the surface, warming the air above. That heated air rises quickly and begins to swirl, carrying debris upward. But only in Mars’ thinner atmosphere could the spinning column grow to its monstrous size.