The Kepler-33 System
Kepler-33 is a planetary system in the constellation Cygnus hosting 5 confirmed exoplanets, about 3,944 light-years from Earth.
Size Comparison: The Planets of Kepler-33
Kepler-33: Star and Habitable Zone
Kepler-33
- Surface temperature
- 5,904 K (Sun: 5,772 K)
- Mass
- 1.29 M☉
- Radius
- 1.82 R☉
- Luminosity
- 3.5975 L☉
- Age
- 4.3 billion years (Sun: 4.6)
Habitable zone of Kepler-33: 1.413–3.317 AU (conservative: 1.789–3.145 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 5 Planets in the Kepler-33 System
| Planet | Type | Orbit | Radius | ESI | Discovered |
|---|---|---|---|---|---|
| Kepler-33 b | Super Earth | 5.7 d | 1.74 R⊕ | 0.27 | 2011 |
| Kepler-33 c | Sub Neptune | 13 d | 3.20 R⊕ | 0.21 | 2011 |
| Kepler-33 d | Neptune-like | 22 d | 5.35 R⊕ | 0.15 | 2011 |
| Kepler-33 e | Neptune-like | 32 d | 4.02 R⊕ | 0.19 | 2011 |
| Kepler-33 f | Neptune-like | 41 d | 4.46 R⊕ | 0.18 | 2011 |
Discovery History
The first planet found here, Kepler-33 b, was discovered in 2011 using the transit method.
- 2011 — Kepler-33 b (Transit)
- 2011 — Kepler-33 c (Transit)
- 2011 — Kepler-33 d (Transit)
- 2011 — Kepler-33 e (Transit)
- 2011 — Kepler-33 f (Transit)
Frequently Asked Questions About Kepler-33
How many planets does Kepler-33 have?
Kepler-33 has 5 confirmed exoplanets. More may await discovery.
Are any planets in the Kepler-33 system habitable?
None of the known planets in Kepler-33 orbit within the star's habitable zone.
How far away is Kepler-33?
Kepler-33 is about 3,944 light-years from Earth in the constellation Cygnus.
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