Could Proxima B Host Alien Life? A Giant Flare May Have Wiped It Out Last Year

A giant flare from the star Proxima Centauri occurred on March 24, 2017. Roberto Molar Candanosa / Carnegie Institution for Science, NASA/SDO, NASA/JPL

The chances of finding life beyond our solar system faced a dramatic new calculation as of March 24, 2017, thanks to a gigantic outburst from one of the stars nearest to us. According to a new paper due to be published in The Astrophysical Journal Letters, the area around Proxima Centauri—which scientists believe could be a solar system—is looking a lot less appealing than it did before that date.

Proxima Centauri let loose a flare that sent charged particles flying toward any planet in its orbit. Although it lasted just 10 seconds, it made the star appear about 1,000 times brighter than usual and was about 10 times brighter than the most impressive flares from our sun that scientists have studied. The paper suggests those kinds of outbursts could be common—and deadly.

"March 24, 2017 was no ordinary day for Proxima Cen," first author Meredith MacGregor, an astronomer at the Carnegie Institution for Science, said in a 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."

As a result, there may not be as complex a solar system as astronomers had thought.

Read more: Proxima Centauri: Our closest cosmic neighbor may have an entire solar system we never knew about

In the fall, scientists published findings suggesting the star was surrounded by a vast cloud of the type of dust that comes together to form planets. But looking at the same data with the flare in mind, the scientists behind the new paper realized Proxima Centauri may not contain such dust.

That means the known planet in the area, Proxima Centauri b, may not have neighboring planets. Even if it does, the flares would mean they are not likely particularly comfortable.