Overview
- An international team reports a four-planet system around the red dwarf LHS 1903 located roughly 116–120 light-years from Earth.
- The innermost world is a dense ~1.4‑Earth‑radius rocky planet, the next two are larger and gas-rich, and the outer planet (LHS 1903 e) is ~1.7 Earth radii with Earth-like density.
- The architecture was established using NASA’s TESS for initial detection, ESA’s Cheops for precise radii, and ground-based spectrographs for masses.
- Analyses disfavor orbital swapping or violent collisions stripping a gas envelope, supporting sequential, inside-out formation in a depleted disk.
- Researchers plan atmospheric follow-up, potentially with JWST, and continued monitoring to search for additional longer-period planets.