The star
The star
LHS 1903
- Type
- M
- Surface
- ≈ 3,664 K
- Size
- 0.54 × the Sun
- Mass
- 0.54 × the Sun
- Brightness
- 0.0474 × the Sun
- Habitable zone
- 0.178–0.457 AU
The planets
LHS 1903
LHS 1903 b
- Year
- 2.16 days
- Distance from star
- 0.0266 AU
- Mass
- 3.3 Earths
- Size
- 1.4 × Earth
- Temperature
- ≈ 796 K (+523 °C)
- Found
- 2026, transit (Transiting Exoplanet Survey Satellite (TESS))
LHS 1903
LHS 1903 c
- Year
- 6.23 days
- Distance from star
- 0.0539 AU
- Mass
- 4.5 Earths
- Size
- 2 × Earth
- Temperature
- ≈ 559 K (+286 °C)
- Found
- 2026, transit (Transiting Exoplanet Survey Satellite (TESS))
LHS 1903
LHS 1903 d
- Year
- 12.57 days
- Distance from star
- 0.086 AU
- Mass
- 6 Earths
- Size
- 2.5 × Earth
- Temperature
- ≈ 442 K (+169 °C)
- Found
- 2026, transit (Transiting Exoplanet Survey Satellite (TESS))
LHS 1903
LHS 1903 e
- Year
- 29.32 days
- Distance from star
- 0.151 AU
- Mass
- 5.8 Earths
- Size
- 1.7 × Earth
- Temperature
- ≈ 333 K (+60 °C)
- Found
- 2026, transit (CHaracterising ExOPlanets Satellite (CHEOPS))
Masses found by the wobble method are minimums, because the orbit's tilt is unknown. Temperatures are equilibrium estimates for a bare planet, before any atmosphere.
How we know
The shadow
The planet passes in front of its star and dims it by a fraction of a percent, every orbit. The dip gives the planet's size and year.
Sources
- Planet and star parameters: NASA Exoplanet Archive, Planetary Systems Composite Parameters, retrieved 1 Nov 2026. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with NASA under the Exoplanet Exploration Program.
- Position: HYG Database v4.1 (CC BY-SA 4.0).
- Habitable zone: a simple estimate from the star's brightness (√L × 0.95 to 1.67 AU), shown as a guide.