Helium clues reveal atmosphere on rocky exoplanet in the habitable zone

Astronomers detected helium escaping from the rocky exoplanet LHS 1140 b, providing the strongest evidence yet that a terrestrial world in another star’s habitable zone can retain an atmosphere. The signal was observed as the planet transited its star using the WINERED spectrograph, indicating a thin upper atmosphere and enabling atmospheric study of potentially habitable worlds, though it does not prove habitability. Future observations will aim to characterize the rest of the atmosphere and investigate whether oceans or other life-friendly features might exist on LHS 1140 b.