Astronomers have come to the conclusion that solid planets, similar in size to Earth and orbiting around a red star, could not sustain life as we know it.
The search for life in the Universe is an activity that currently represents the interest of many scientists, as well as an important part of the general public. Unfortunately, such a mission, no matter how noble it may seem, is an extremely complex task. First of all, we must not forget that the Universe is extremely large and that, to date, only a fraction of the sky we see in the evening has been scanned by scientists. Secondly, another problem is represented by the object of our search. More precisely, although we seek the extraterrestrial life, the truth is that scientists operate largely based upon their own assumptions and from what exists on the Earth related to evolution and signs of life.
In a recent study, astronomers have narrowed this search down by eliminating an entire class of planets. Thus, starting from the exoplanet LHS 3844b, which is 48 light-years away from our planet (in the constellation Indus) – a world made of rock which is only 30% larger than our planet but orbiting a red sun – scientists have come to the conclusion that it is too hot to have an atmosphere and, implicitly, to support life on it.
The possibility that these Earth-like planets orbiting a red star could host life is a debate that has been taking place for some years in the academic world. However, this study on planet LHS 3844b could put an end to this debate.
The study concluded that exoplanets that revolve around their star in a manner similar to the Moon could not accommodate an atmosphere suitable for life.
“To have life as we know it, you need liquid water,” explains Abraham Leob, an astronomer at Harvard University’s Center for Astrophysics. He added that liquid water can exist on the surface of a planet only under the presence of an atmosphere.
This finding could be used to redefine the conditions that a planet must meet in order to sustain life on it.