The star
The star
Kepler-256
- Type
- yellow star
- Surface
- ≈ 5,551 K
- Size
- 1.30 × the Sun
- Mass
- 1.04 × the Sun
- Brightness
- 0.873 × the Sun
- Habitable zone
- 0.711–1.68 AU
The planets
Kepler-256
Kepler-256 b
- Year
- 1.62 days
- Distance from star
- 0.027 AU
- Mass
- 3.1 Earths
- Size
- 1.6 × Earth
- Temperature
- ≈ 1681 K (+1408 °C)
- Found
- 2014, transit (Kepler)
Kepler-256
Kepler-256 c
- Year
- 3.39 days
- Distance from star
- 0.045 AU
- Mass
- 5.3 Earths
- Size
- 2.1 × Earth
- Temperature
- ≈ 1315 K (+1042 °C)
- Found
- 2014, transit (Kepler)
Kepler-256
Kepler-256 d
- Year
- 5.84 days
- Distance from star
- 0.064 AU
- Mass
- 6.7 Earths
- Size
- 2.5 × Earth
- Temperature
- ≈ 1097 K (+824 °C)
- Found
- 2014, transit (Kepler)
Kepler-256
Kepler-256 e
- Year
- 10.68 days
- Distance from star
- 0.096 AU
- Mass
- 6.1 Earths
- Size
- 2.4 × Earth
- Temperature
- ≈ 897 K (+624 °C)
- Found
- 2014, transit (Kepler)
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.