In September of 2021, the Perseverance rover was working quietly on the surface of Mars when this happened: [AUDIO: dust devil]. It might not sound like much, but on Mars, it’s the most exciting thing you’re ever likely to see: a dust devil — a spinning column of air that’s like a mini-tornado. This one swept over the top of the rover, blowing away some of the dust that had settled on it.

Dust devils are common sights on Mars, just as they are in many regions of Earth. They form when the ground is warmed by the Sun, causing the air above it to rise. It forms a spinning vortex that crawls along the landscape. On Mars, dust devils can be more than a mile high and half a mile wide — much larger than on Earth. And as they blow the dust off the Martian rocks, they leave winding trails that look like abstract tattoos.

Dust devils may generate small crackles of electricity: lightning. They’re too small and faint to see. But giant dust storms may produce more powerful outbursts. Research says even those shouldn’t be strong enough to harm either people or their machines. But they might produce a soft glow around a storm — the glow of dust blowing in the Martian winds.

Look for Mars well up in the west at nightfall. It looks like a fairly bright orange star. Tonight, it lines up with the twins of Gemini. The stars are to the right of Mars, with brighter Pollux closer to it.
 

Script by Damond Benningfield

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