On planets orbiting near M-dwarfs suggested not to look for extraterrestrial life
A team of astrophysicists from the University of California has found a way to narrow the search for extraterrestrial life. According to a study published in the Astrophysical Journal Letters, the planets orbiting M dwarfs without an atmosphere, also do not have it, and therefore there is no point to look for living organisms.
These conclusions were reached during the observation of the planet GJ 1252b. Its rotation cycle around its parent star is one Earth day. It is slightly larger than Earth and much closer to the star than our planet is to the Sun, making it extremely hot. The pressure from the star’s radiation is so powerful that it has destroyed the atmosphere of GJ 1252b. Similar processes can be observed on Mercury, but there the elevated temperatures have not yet completely destroyed the atmosphere.
For the study, the experts measured the infrared radiation of the planet. It turned out that the daytime temperatures of GJ 1252b reach 1227 degrees Celsius. The high temperature combined with the assumed low surface pressure led the researchers to the idea that the planet has no atmosphere. Accordingly, the authors propose to exclude such planets from the number of those where we should look for extraterrestrial life. At the same time, the scientists believe that the planets, which are at a sufficient distance from the M-dwarf, may still have an atmosphere.