WORLD NEWS
A rocky planet in the habitable zone now has a strong atmosphere signal
Astronomers reported helium escaping from LHS 1140 b, making it the clearest case yet that a rocky exoplanet in a habitable zone has retained an atmosphere. It is not a life detection, but it changes how scientists can search for air around Earth-like worlds.
What was found
A study released on 16 July 2026 reports helium absorption from LHS 1140 b, consistent with gas escaping from the planet’s atmosphere. The planet is about 48 light-years away and orbits a low-mass red dwarf inside the star’s habitable zone, where temperatures could allow liquid water if other conditions are right.
What evidence supports it
The evidence comes from transit spectroscopy, in which a planet passes in front of its star and a thin atmospheric signal can imprint itself on starlight. The team used the WINERED spectrograph on the Magellan telescope at Las Campanas Observatory in Chile and detected escaping helium during 2024 observations. The inner planet LHS 1140 c did not show the same signal.
How it changes the picture
The result matters because the open question was whether rocky planets around cool stars can hold onto atmospheres for billions of years. The Center for Astrophysics describes the finding as the first clear atmosphere detection for a rocky planet in another star’s habitable zone, and the paper interprets the signal as a helium-dominated upper atmosphere depleted in hydrogen. NASA’s catalog lists LHS 1140 b as discovered in 2017, with a radius of 1.73 Earths and a 24.7-day orbit.
What remains unknown
The finding does not mean oceans or life have been found. Helium absorption appeared in 2024 but was not comparably detected in 2025, which means atmospheric escape may vary with time. Helium in the upper atmosphere is also only one layer of evidence; researchers still need to determine whether heavier gases such as nitrogen, carbon dioxide or water vapor exist lower down.
Next checks and primary sources
The next step is repeated transit observation at more wavelengths. The Science paper records the helium result, the arXiv abstract summarizes the 2024 detection and 2025 non-detection, and the NASA catalog gives the stable planetary context. Only future observations can narrow the atmosphere’s composition and show whether LHS 1140 b is a practical target for life-related chemistry.
CfA official release and researcher explanation
Science paper DOI and publication record