Paul VoosenTwo years ago, Mars went undercover. Martian dust storms are common, but every decade or so, for reasons unknown, a monstrous one goes global, veiling the planet.
The storms can be a mortal threat to exploration: The one in 2018 killed off NASA’s Opportunity rover by coating its solar panels in dust.
But now, researchers say the storms may also be one of the culprits in the ultimate martian cold case: how the once-wet planet lost its water.Fossilized rivers and deltas etched across Mars suggest water flowed there billions of years ago.