Kepler-55 b
Kepler-55 b is a mini-Neptune orbiting Kepler-55 in the constellation Lyra. It lies about 1,888 light-years from Earth and was discovered in 2012 using the transit method.
How Big Is Kepler-55 b?
Kepler-55 b has a radius of 2.43 times that of Earth.
Is Kepler-55 b in the Habitable Zone?
The position of Kepler-55 b relative to the habitable zone of Kepler-55 cannot be precisely determined from the available orbital data.
Habitable zone of Kepler-55: 0.266–0.660 AU (conservative: 0.336–0.626 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 ›
Orbit and Year Length
A year on Kepler-55 b — one full orbit around Kepler-55 — lasts 27.9 Earth days, shorter than Mercury's 88-day year.
How Was Kepler-55 b Discovered?
Kepler-55 b was discovered in 2012 using the transit method, with observations from Kepler.
The transit method watches a star for the tiny, regular dip in brightness that occurs when a planet crosses in front of it. The depth and timing of these dips reveal the planet's size and orbital period.
How Far Away Is Kepler-55 b?
Kepler-55 b is 1,887.8 light-years (578.8 parsecs) from Earth. Light arriving here tonight left the planet about 1,888 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 33,225,280 years to make the journey.
Earth Similarity Index
The Earth Similarity Index (ESI) scores how physically similar a planet is to Earth, from 0 to 1, based on radius, density, escape velocity and surface temperature. Kepler-55 b scores 0.40, ranking #485 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-55
Kepler-55
- Surface temperature
- 4,362 K (Sun: 5,772 K)
- Mass
- 0.62 M☉
- Radius
- 0.58 R☉
The Kepler-55 Planetary System
Kepler-55 b is one of 5 known planets in the Kepler-55 system. Its siblings:
- Kepler-55 c (Mini Neptune)
- Kepler-55 d (Super Earth)
- Kepler-55 e (Super Earth)
- Kepler-55 f (Super Earth)
Kepler-55 b — Complete Data
| Radius | 2.430 Earth radii (0.217 Jupiter radii) |
|---|---|
| Orbital period | 27.95 days |
| Earth Similarity Index | 0.40 |
| Distance from Earth | 1,887.8 light-years (578.8 parsecs) |
| Constellation | Lyra |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2012 |
Data: NASA Exoplanet Archive, last updated 2021-09-20. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-55 b
Is Kepler-55 b habitable?
Kepler-55 b is not known to orbit within the habitable zone of Kepler-55, and as a mini-Neptune it is an unlikely candidate for life as we know it.
How far away is Kepler-55 b?
Kepler-55 b is about 1,888 light-years from Earth in the constellation Lyra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 33,225,280 years to get there.
How big is Kepler-55 b compared to Earth?
Kepler-55 b has 2.43 times the radius of Earth.
How long is a year on Kepler-55 b?
One orbit around Kepler-55 takes 27.9 Earth days — short enough that 13 of its years would fit into one Earth year.
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