The Kepler-121 System
Kepler-121 is a planetary system in the constellation Lyra hosting 2 confirmed exoplanets, about 1,665 light-years from Earth.
Size Comparison: The Planets of Kepler-121
Kepler-121: Star and Habitable Zone
Kepler-121
- Surface temperature
- 5,311 K (Sun: 5,772 K)
- Radius
- 0.70 R☉
Habitable zone of Kepler-121: 0.457–1.091 AU (conservative: 0.578–1.035 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 2 Planets in the Kepler-121 System
| Planet | Type | Orbit | Radius | ESI | Discovered |
|---|---|---|---|---|---|
| Kepler-121 b | Mini Neptune | 3.2 d | 2.34 R⊕ | 0.24 | 2014 |
| Kepler-121 c | Mini Neptune | 41 d | 2.27 R⊕ | 0.40 | 2014 |
Discovery History
The first planet found here, Kepler-121 b, was discovered in 2014 using the transit method.
- 2014 — Kepler-121 b (Transit)
- 2014 — Kepler-121 c (Transit)
Frequently Asked Questions About Kepler-121
How many planets does Kepler-121 have?
Kepler-121 has 2 confirmed exoplanets. More may await discovery.
Are any planets in the Kepler-121 system habitable?
None of the known planets in Kepler-121 orbit within the star's habitable zone.
How far away is Kepler-121?
Kepler-121 is about 1,665 light-years from Earth in the constellation Lyra.
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