Kepler-406 c
Kepler-406 c is a terrestrial planet orbiting Kepler-406 in the constellation Cygnus. It lies about 1,187 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is Kepler-406 c?
Kepler-406 c has a radius of 0.85 times that of Earth. Its mass is 2.7 times that of Earth, giving it a density of 24.39 g/cm³ — comparable to rocky planets like Earth (5.51 g/cm³).
Is Kepler-406 c in the Habitable Zone?
The position of Kepler-406 c relative to the habitable zone of Kepler-406 cannot be precisely determined from the available orbital data.
Habitable zone of Kepler-406: 0.748–1.775 AU (conservative: 0.948–1.683 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-406 c — one full orbit around Kepler-406 — lasts 4.62 Earth days, shorter than Mercury's 88-day year.
How Was Kepler-406 c Discovered?
Kepler-406 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-406 c?
Kepler-406 c is 1,187.3 light-years (364.0 parsecs) from Earth. Light arriving here tonight left the planet about 1,187 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 20,896,480 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-406 c scores 0.29, ranking #1,590 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-406
Kepler-406
- Surface temperature
- 5,538 K (Sun: 5,772 K)
- Mass
- 1.07 M☉
- Radius
- 1.07 R☉
- Age
- 5.8 billion years (Sun: 4.6)
The Kepler-406 Planetary System
Kepler-406 c is one of 2 known planets in the Kepler-406 system. Its siblings:
- Kepler-406 b (Super Earth)
Kepler-406 c — Complete Data
| Radius | 0.850 Earth radii (0.076 Jupiter radii) |
|---|---|
| Mass | 2.71 Earth masses (0.009 Jupiter masses) |
| Density | 24.39 g/cm³ (Earth: 5.51) |
| Orbital period | 4.62 days |
| Earth Similarity Index | 0.29 |
| Distance from Earth | 1,187.3 light-years (364.0 parsecs) |
| Constellation | Cygnus |
| 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-406 c
Is Kepler-406 c habitable?
Kepler-406 c is not known to orbit within the habitable zone of Kepler-406, and as a terrestrial planet it is an unlikely candidate for life as we know it.
How far away is Kepler-406 c?
Kepler-406 c is about 1,187 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 20,896,480 years to get there.
How big is Kepler-406 c compared to Earth?
Kepler-406 c has 0.85 times the radius of Earth and about 2.7 times its mass.
How long is a year on Kepler-406 c?
One orbit around Kepler-406 takes 4.6 Earth days — short enough that 79 of its years would fit into one Earth year.
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