Overview
- LHS 3844 b’s dayside heat, measured by JWST’s Mid‑Infrared Instrument from 5 to 12 micrometers, shows direct surface emission with no detectable atmosphere.
- The spectrum rules out an Earth‑like, silica‑rich crust and instead matches basaltic or mantle‑like rocks rich in magnesium and iron, consistent with olivine.
- Researchers find two surface histories fit the data, either fresh basalt from recent volcanism or an older surface coated in dark, space‑weathered regolith.
- Sulfur dioxide, a gas often linked to active volcanism, was not seen in the JWST data, which tips the balance toward a long‑weathered regolith surface.
- The team has secured follow‑up JWST observations to use angle‑dependent emission to tell solid rock from powdery regolith, while a new POSEIDON v1.4 tool models coupled surface‑atmosphere signals and is already benchmarking other rocky worlds like TOI‑1685 b and 55 Cancri e.