The Kepler-42 System
Kepler-42 is a planetary system in the constellation Cygnus hosting 3 confirmed exoplanets, about 131 light-years from Earth.
Size Comparison: The Planets of Kepler-42
Kepler-42: Star and Habitable Zone
Kepler-42
- Spectral type
- M
- Surface temperature
- 3,068 K (Sun: 5,772 K)
- Mass
- 0.13 M☉
- Radius
- 0.17 R☉
- Luminosity
- 0.0024 L☉
- Age
- 4.5 billion years (Sun: 4.6)
Habitable zone of Kepler-42: 0.040–0.107 AU (conservative: 0.051–0.101 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 3 Planets in the Kepler-42 System
| Planet | Type | Orbit | Radius | ESI | Discovered |
|---|---|---|---|---|---|
| Kepler-42 b | Terrestrial | 1.2 d | 0.78 R⊕ | 0.36 | 2011 |
| Kepler-42 c | Terrestrial | 0.5 d | 0.73 R⊕ | 0.30 | 2011 |
| Kepler-42 d | Terrestrial | 1.9 d | 0.57 R⊕ | 0.39 | 2011 |
Discovery History
The first planet found here, Kepler-42 b, was discovered in 2011 using the transit method.
- 2011 — Kepler-42 b (Transit)
- 2011 — Kepler-42 c (Transit)
- 2011 — Kepler-42 d (Transit)
Frequently Asked Questions About Kepler-42
How many planets does Kepler-42 have?
Kepler-42 has 3 confirmed exoplanets. More may await discovery.
Are any planets in the Kepler-42 system habitable?
None of the known planets in Kepler-42 orbit within the star's habitable zone.
How far away is Kepler-42?
Kepler-42 is about 131 light-years from Earth in the constellation Cygnus.
Explore the Kepler-42 system in the app
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