By detecting helium escaping into space, astronomers have found the first direct evidence of an atmosphere on LHS 1,140 b, a rocky exoplanet located in its star’s habitable zone.
A collaborative team of researchers recently announced the discovery of an atmosphere on a rocky exoplanet orbiting in the habitable zone of its star. While this finding is intriguing for the search for life beyond Earth, the atmosphere is not only comprised of helium, but it was found to be escaping the exoplanet. The researchers discuss these findings in a recent study published in the journal Science and it holds the potential to help scientists better understand the formation and evolution of rocky exoplanets while narrowing the search for life beyond Earth.
For the study, the researchers analyzed data about LHS 1,140 b, which orbits a red dwarf star about 50 light-years from Earth and has a radius and mass about 1.7 and 5.6 of Earth, respectively, designating LHS 1,140 b as a super-Earth. While the researchers note this is the first time an atmosphere has been detected around a rocky exoplanet orbiting in the habitable zone of its star, LHS 1,140 b’s atmosphere is primarily comprised of helium and was also found to be escaping the exoplanet or being stripped away.
This is because red dwarf stars have been found to be significantly more active than Sun-like stars, meaning its intense radiation is potentially stripping LHS 1,140 b’s upper atmosphere where the helium is found. Despite this, the team noted other types of gases could be present in the lower altitudes of the atmosphere.
