The star
The star
Kepler-87
- Type
- yellow star
- Surface
- ≈ 5,600 K
- Size
- 1.82 × the Sun
- Mass
- 1.10 × the Sun
- Brightness
- 2.12 × the Sun
- Habitable zone
- 1.1–2.61 AU
The planets
Kepler-87
Kepler-87 b
- Year
- 114.74 days
- Distance from star
- 0.481 AU
- Mass
- 1 Jupiters
- Size
- 13 × Earth
- Temperature
- ≈ 478 K (+205 °C)
- Found
- 2013, transit (Kepler)
Kepler-87
Kepler-87 c
- Year
- 191.23 days
- Distance from star
- 0.676 AU
- Mass
- 6.4 Earths
- Size
- 6.1 × Earth
- Temperature
- ≈ 403 K (+130 °C)
- Found
- 2013, 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.