Kepler-26 c
Kepler-26 c is a mini-Neptune orbiting Kepler-26 in the constellation Lyra. It lies about 1,094 light-years from Earth and was discovered in 2011 using the transit method.
How Big Is Kepler-26 c?
Kepler-26 c has a radius of 2.72 times that of Earth. Its mass is 6.2 times that of Earth, giving it a density of 1.61 g/cm³ — closer to gas planets like Jupiter (1.33 g/cm³).
Is Kepler-26 c in the Habitable Zone?
The position of Kepler-26 c relative to the habitable zone of Kepler-26 cannot be precisely determined from the available orbital data.
Habitable zone of Kepler-26: 0.191–0.485 AU (conservative: 0.242–0.460 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 ›
Temperature on Kepler-26 c
Kepler-26 c receives 4.82 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on Kepler-26 c — one full orbit around Kepler-26 — lasts 17.3 Earth days, shorter than Mercury's 88-day year.
How Was Kepler-26 c Discovered?
Kepler-26 c was discovered in 2011 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-26 c?
Kepler-26 c is 1,093.6 light-years (335.3 parsecs) from Earth. Light arriving here tonight left the planet about 1,094 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 19,247,360 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-26 c scores 0.37, ranking #650 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-26
Kepler-26
- Surface temperature
- 3,914 K (Sun: 5,772 K)
- Mass
- 0.54 M☉
- Radius
- 0.51 R☉
The Kepler-26 Planetary System
Kepler-26 c is one of 4 known planets in the Kepler-26 system. Its siblings:
- Kepler-26 b (Puffy Planet)
- Kepler-26 d (Terrestrial)
- Kepler-26 e (Mini Neptune)
Kepler-26 c — Complete Data
| Radius | 2.720 Earth radii (0.243 Jupiter radii) |
|---|---|
| Mass | 6.20 Earth masses (0.020 Jupiter masses) |
| Density | 1.61 g/cm³ (Earth: 5.51) |
| Orbital period | 17.26 days |
| Stellar irradiation | 4.82× Earth |
| Earth Similarity Index | 0.37 |
| Distance from Earth | 1,093.6 light-years (335.3 parsecs) |
| Constellation | Lyra |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2011 |
Data: NASA Exoplanet Archive, last updated 2016-04-13. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-26 c
Is Kepler-26 c habitable?
Kepler-26 c is not known to orbit within the habitable zone of Kepler-26, and as a mini-Neptune it is an unlikely candidate for life as we know it.
How far away is Kepler-26 c?
Kepler-26 c is about 1,094 light-years from Earth in the constellation Lyra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 19,247,360 years to get there.
How big is Kepler-26 c compared to Earth?
Kepler-26 c has 2.72 times the radius of Earth and about 6.2 times its mass.
How long is a year on Kepler-26 c?
One orbit around Kepler-26 takes 17.3 Earth days — short enough that 21 of its years would fit into one Earth year.
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