Kepler-156 c
Kepler-156 c is a mini-Neptune orbiting Kepler-156 in the constellation Lyra. It lies about 1,446 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is Kepler-156 c?
Kepler-156 c has a radius of 2.55 times that of Earth.
Is Kepler-156 c in the Habitable Zone?
Kepler-156 c orbits inside the inner edge of the habitable zone of Kepler-156. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of Kepler-156: 0.489–1.178 AU (conservative: 0.619–1.117 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-156 c — one full orbit around Kepler-156 — lasts 15.9 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.117 AU — closer to its star than Mercury is to the Sun.
How Was Kepler-156 c Discovered?
Kepler-156 c was discovered in 2014 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-156 c?
Kepler-156 c is 1,446.4 light-years (443.5 parsecs) from Earth. Light arriving here tonight left the planet about 1,446 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 25,456,640 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-156 c scores 0.28, ranking #2,417 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-156
Kepler-156
- Surface temperature
- 5,094 K (Sun: 5,772 K)
- Radius
- 0.81 R☉
The Kepler-156 Planetary System
Kepler-156 c is one of 2 known planets in the Kepler-156 system. Its siblings:
- Kepler-156 b (Mini Neptune)
Kepler-156 c — Complete Data
| Radius | 2.550 Earth radii (0.227 Jupiter radii) |
|---|---|
| Orbital period | 15.91 days |
| Orbital distance | 0.117 AU |
| Earth Similarity Index | 0.28 |
| Distance from Earth | 1,446.4 light-years (443.5 parsecs) |
| Constellation | Lyra |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2014 |
Data: NASA Exoplanet Archive, last updated 2014-05-14. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-156 c
Is Kepler-156 c habitable?
No — Kepler-156 c orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is Kepler-156 c?
Kepler-156 c is about 1,446 light-years from Earth in the constellation Lyra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 25,456,640 years to get there.
How big is Kepler-156 c compared to Earth?
Kepler-156 c has 2.55 times the radius of Earth.
How long is a year on Kepler-156 c?
One orbit around Kepler-156 takes 15.9 Earth days — short enough that 23 of its years would fit into one Earth year.