Cambridge Study Deems 4 Barnard's Star Planets Uninhabitable After 2 Billion Years of Atmosphere Loss
Updated
Updated · Universe Today · Jul 20
Cambridge Study Deems 4 Barnard's Star Planets Uninhabitable After 2 Billion Years of Atmosphere Loss
1 articles · Updated · Universe Today · Jul 20
Summary
Four exoplanets around Barnard's Star are likely uninhabitable, with Cambridge researchers concluding they lost their atmospheres after roughly 2 billion years.
Barnard's Star's high magnesium content likely made the planets rich in periclase, a magnesium-oxide mineral that stores water poorly, while their tight orbits exposed them to radiation and flares for about 10 billion years.
At just 1% to 4% of the Earth-Sun distance, all four worlds are likely tidally locked, and the outermost still circles about 10 times closer to its star than Mercury does to the Sun.
The study also found the three inner planets sit in a 9:12:16 orbital resonance that may stabilize an otherwise compact, collision-prone system.
Barnard's Star, less than 6 light-years away, has had four planets confirmed since August 2024, and the team said the work could help future missions such as ESA's PLATO judge habitability on other small rocky worlds.