Rocky Exoplanets LHS 1140 b and TRAPPIST‑1 b Confirmed to Have Atmospheres

Astronomers have, for the first time, detected a clear atmosphere on the rocky super‑Earth LHS 1140 b, which orbits a red dwarf about 48 light‑years from Earth. Using the WINERED spectrograph on the Magellan Clay telescope in Chile, researchers led by Collin Cherubim of Harvard identified escaping helium, indicating the planet has retained a gaseous envelope for billions of years and is a prime target for future James Webb observations.

Separate observations with the James Webb Space Telescope suggest that the rocky planet TRAPPIST‑1 b, 40 light‑years away, may also possess a dense carbon‑dioxide‑rich atmosphere. Analysis by astronomers at the Max Planck Institute and Spain’s INTA‑CSIC challenges earlier assumptions that the world lacked an atmosphere, pointing to possible volcanic or tectonic activity and temperature‑inversion effects. The discoveries demonstrate that rocky worlds in habitable zones can sustain atmospheres, expanding the pool of exoplanets suitable for detailed study with JWST and upcoming missions such as PLATO.