Exoplanet
K2-138 b
660.74 light-years
- Discovery
- Transit · 2017
- Radius
- 1.51 (+0.11 / −0.084) Earth radii
- Mass
- 3.1 (+1.05 / −1.05) Earth masses
- Orbital period
- 2.3531 (+2.2 × 10⁻⁴ / −2.2 × 10⁻⁴) days
- Semi-major axis
- 0.0339 (+2.3 × 10⁻⁴ / −2.9 × 10⁻⁴) AU
- Equilibrium temperature
- 1,157 (+78 / −74) K
- Mass provenance
- Mass
Measurements may come from different studies and need not form one self-consistent model. “Msini” is a minimum mass; a mass inferred from radius is an estimate. Equilibrium temperature is a model estimate, not a measured surface temperature or evidence of habitability.
NASA archive record and references ↗
Snapshot retrieved: 2026-10-11T04:15:07.688253+00:00