Key idea: A discovery about planets around M dwarf stars could cause a major shift in the search for life on other planets.
Original author and publication date: University of California, Riverside – October 21, 2022
Futurizonte Editor’s Note: The Universe keeps reminding us that we have no idea about what truly is out there
From the article:
An Earth-like planet orbiting an M dwarf — the most common type of star in the universe — appears to have no atmosphere at all. This discovery could cause a major shift in the search for life on other planets.
Because M-dwarfs are so ubiquitous, this discovery means a large number of planets orbiting these stars may also lack atmospheres and therefore are unlikely to harbor living things.
The work that led to the revelations about the no-atmosphere planet, named GJ 1252b, are detailed in the Astrophysical Journal Letters.
This planet orbits its star twice during the course of a single day on Earth. It is slightly larger than Earth, and it is much closer to its star than Earth is to the sun, making GJ 1252b intensely hot as well as inhospitable.
“The pressure from the star’s radiation is immense, enough to blow a planet’s atmosphere away,” said Michelle Hill, UC Riverside astrophysicist and study co-author.
Earth also loses some of its atmosphere over time because of the sun, but volcanic emissions and other carbon cycling processes make the loss barely noticeable by helping replenish what is lost. However, in greater proximity to a star, a planet cannot keep replenishing the amount being lost.
In our solar system, this is the fate of Mercury. It does have an atmosphere, but one that is extremely thin, made up of atoms blasted off its surface by the sun. The extreme heat of the planet causes these atoms to escape into space.