Overview
- A paper published this week reports ground‑based spectroscopic detection of helium around LHS 1140 b, a rocky planet about 48 light‑years away that orbits in its star’s habitable zone.
- The observed helium absorption traces an extended, escaping upper atmosphere and is taken by the authors as direct evidence the planet retains an atmosphere.
- Modeling in the study reconstructs atmospheric escape and suggests the upper layers are helium‑dominated and may have persisted for roughly three billion years while deeper layers could host heavier gases.
- Earlier follow‑up attempts in 2025 failed to reproduce the signal, so astronomers are calling for independent confirmations with JWST, HST and more ground‑based monitoring before the result is settled.
- If confirmed, LHS 1140 b would become a top target for further study and would affect ideas about how planets around red dwarfs can keep atmospheres, but there remains no evidence of life and the lower atmosphere and surface conditions are still unknown.