“March 24, 2017, was no ordinary day for Proxima Cen,” said Meredith MacGregor, an astronomer from the Carnegie Institution for Science, in a National Radio Astronomy Observatory press release.

Tough Conditions

MacGregor’s team found that the flare made Proxima Centauri 1,000 times brighter over the course of just 10 seconds. Though the entire event (including a smaller preceding flare) lasted less than two minutes, it bathed little Proxima b with an estimated 4,000 times more radiation than Earth receives from the Sun’s usual flares.

That’s not great news for anything that might have been alive on the exoplanet’s surface.

“It’s likely that Proxima b was blasted by high energy radiation during this flare,” said MacGregor in the press release. “Over the billions of years since Proxima b formed, flares like this one could have evaporated any atmosphere or ocean and sterilized the surface, suggesting that habitability may involve more than just being the right distance from the host star to have liquid water.”