Humanity’s romantic notion that extraterrestrial life might be lurking just beyond our reach has been dealt a serious blow. A new study published in Astrophysical Journal Letters reveals that Earth’s closest exoplanet neighbor, Proxima B, was recently slammed by a colossal stellar flare that bombarded the planet with radiation. That’s obviously not great news for the possibility of life thriving there, and any organisms that call the planet home would not have had a pleasant few days.
Proxima B resides within the habitable zone of its star, Proxima Centauri. Astronomers and alien hunters have long looked to the nearby system as our best chance of discovering extraterrestrial life, given that it is less than five light years away from our own. Scientists have noted that the planet could be “Earth-like,” which is incredibly exciting if you dream of one day reading news about ET, but this recent stellar event could put a serious damper on that enthusiasm.
The team discovered the flare after combing through data gathered from 2017. The flare occurred in March, and increased the brightness of Proxima Centauri by 1,000 times in mere seconds. That’s an incredible amount of energy, and it’s at least ten times brighter than the largest flares our own Sun produces.
“It’s likely that Proxima b was blasted by high energy radiation during this flare,” Meredith MacGregor of the Carnegie Institute for Science explains. “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.”
In short, the flare detected by the researchers is likely one of many that have slammed into Proxima B over its lifetime, and if Proxima Centauri has a habit of blowing off steam in this manner there’s little hope that its nearby “habitable” planet is actually habitable at all. If live ever existed on the planet, it would have had a very hard time hanging on through events such as this.