The Kepler-251 System
Kepler-251 is a planetary system in the constellation Cygnus hosting 4 confirmed exoplanets, about 3,016 light-years from Earth.
Size Comparison: The Planets of Kepler-251
Kepler-251: Star and Habitable Zone
Kepler-251
- Surface temperature
- 5,526 K (Sun: 5,772 K)
- Radius
- 0.89 R☉
Habitable zone of Kepler-251: 0.620–1.471 AU (conservative: 0.785–1.395 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.
See the full interactive habitable-zone view in the Exoplanet Explorer app ›
All 4 Planets in the Kepler-251 System
| Planet | Type | Orbit | Radius | ESI | Discovered |
|---|---|---|---|---|---|
| Kepler-251 b | Super Earth | 4.8 d | 1.33 R⊕ | 0.29 | 2014 |
| Kepler-251 c | Mini Neptune | 17 d | 2.77 R⊕ | 0.25 | 2014 |
| Kepler-251 d | Mini Neptune | 30 d | 2.77 R⊕ | 0.28 | 2014 |
| Kepler-251 e | Mini Neptune | 100 d | 2.77 R⊕ | 0.46 | 2014 |
Discovery History
The first planet found here, Kepler-251 b, was discovered in 2014 using the transit method.
- 2014 — Kepler-251 b (Transit)
- 2014 — Kepler-251 c (Transit)
- 2014 — Kepler-251 d (Transit)
- 2014 — Kepler-251 e (Transit)
Frequently Asked Questions About Kepler-251
How many planets does Kepler-251 have?
Kepler-251 has 4 confirmed exoplanets. More may await discovery.
Are any planets in the Kepler-251 system habitable?
None of the known planets in Kepler-251 orbit within the star's habitable zone.
How far away is Kepler-251?
Kepler-251 is about 3,016 light-years from Earth in the constellation Cygnus.
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