Astronomers have detected helium escaping from the atmosphere of exoplanet LHS 1140 b, marking the first solid evidence of an atmosphere around a rocky planet in its star’s habitable zone. The planet, located 48 light-years from Earth, orbits in a region where temperatures could potentially support liquid water.
The discovery, published in the journal Science, represents a crucial step in the search for extraterrestrial life. While no life or biosignatures have been detected, the findings confirm one of the essential conditions for long-term habitability. Collin Cherubim, a researcher at Harvard University who led the study, said: “At this moment we have absolutely no proof of life on the planet. But we believe that all the really important and essential ingredients are there.”
A water world possibility
LHS 1140 b was discovered in 2017 in the constellation Cetus. The planet has a radius 1.7 times that of Earth and a mass 5.6 times greater. Recent observations suggest it might be a water-rich world, possibly covered by a global ocean, rather than an enlarged version of Earth.
The planet completes an orbit around its red dwarf star every 24.7 days. Red dwarf stars are smaller, cooler, and dimmer than the Sun, making planets easier to detect during transits. However, these stars can emit intense flares and ultraviolet radiation that potentially strip away planetary atmospheres.
Detection breakthrough