A gigantic stellar eruption has recently been detected on the surface of Proxima Centauri, the star closest to our solar system. A eruption so powerful that if life was actually present on Proxima b, it probably just disappeared.
Since the announcement of its discovery in August 2016, Proxima B is an infinite source of wonder and the target of many scientific studies. In addition to being the extrasolar planet closest to our solar system, it also orbits in the habitable zone of its star. As a result, astronomers naturally sought to determine if this rocky planet could harbor extraterrestrial life. Many of these studies focused on whether or not Proxima b could maintain an atmosphere and liquid water on its surface, given that its parent star is of the “red dwarf” type.
Red dwarfs are smaller, less massive and weaker than Sun-like stars. On the other hand, they have a much longer lifespan and are very numerous in the Galaxy. Thus, astronomers are increasingly interested in them, life having the opportunity to develop over billions of years. But the red dwarfs have a problem: they are terribly unstable, projecting gigantic stellar eruptions around them. And according to a new study conducted by an international team of scientists, Proxima Centauri would have projected a few days ago one of these bursts — which proved to be destructive.
A sufficiently high blowout rate could permanently prevent the formation of a protective ozone layer on Proxima b. This would lead to levels of UV radiation on the surface that would be beyond what some of the most resistant organisms can withstand. Bad news for life, then. But beyond our nearest star system, this study also has implications for other star systems of this type. Red dwarfs are indeed the most common in our galaxy — about 75% of the star population — and two-thirds of these stars are active. Given this information, measuring the impact of these eruptions on the surrounding worlds is a necessary component to determine if exoplanets located a little too close to their star might or might not be habitable.