Habitable-zone candidate
Kepler-442
One of the most "Earth-like" planets ever found by Kepler — 60% bigger, in HZ.
- Planets
- 1
- Distance
- 1193.6 ly
- Host
- G-type
About Kepler-442
Discovery
Validated in 2015 by Guillermo Torres and colleagues as part of a broader study of small habitable-zone Kepler candidates, Kepler-442b orbits a K-dwarf about 1,200 light-years away in the constellation Lyra.
Why it matters
Kepler-442b consistently ranks at the top of Earth-similarity rankings — a 1.3 R⊕ planet receiving roughly Earth-like insolation, around a quieter, longer-lived K-star than the Sun. K-dwarfs are arguably better habitability hosts than M-dwarfs because they lack the violent flaring.
Current research
Like most Kepler discoveries, the star is too faint for atmospheric characterization; its value is as a statistical benchmark and as a target for future flagship missions like HWO.
Comparable to
A super-Earth slightly larger than our own, in the habitable zone of a star that will outlive the Sun by tens of billions of years.
System geometry
At a glance
- Hostname
- Kepler-442
- Spectral type
- G2V
- Distance
- 1193.6 ly · 365.96 pc
- Stellar mass
- 0.61 M☉
- Stellar radius
- 0.60 R☉
- Luminosity
- 0.117 L☉
- Effective temp
- 4402 K
- Confirmed planets
- 1
- Habitable zone
- 0.325 – 0.469 AU
Top-down orbital diagram
Orbits to scale within this system. Dashed green = habitable-zone edges.
Planet positions are illustrative (evenly spaced in phase). For live motion see the 3D scene.
The planets
1 confirmed.
Rocky world
Kepler-442 b
- Orbit
- 0.409 AU
- Period
- 112.31 days
- Radius
- 1.34 R⊕
- Mass
- 2.36 M⊕
- Eq. temperature
- 241 K
- Eccentricity
- 0.040
- Discovered
- 2015 · Transit
Compared to our Solar System
Each row shows the closest Solar-System analog by radius (log-space). Earth is pinned at the bottom as the constant frame of reference.
| Planet | Radius (R⊕) | Mass (M⊕) | Orbit (AU) | Period (days) | Eq temp (K) | Solar analog |
|---|---|---|---|---|---|---|
| Kepler-442 b | 1.34 | 2.36 | 0.409 | 112.31 | 241 | Earth |
| Earth (reference) | 1.00 | 1.00 | 1.000 | 365.25 | 255 | — |
Research status
◇ JWST observation status
No JWST programs are currently targeting planets in this system. The system may be observed in future cycles or by upcoming missions (Ariel, HWO, Roman).
Discovery timeline
- 2015
Kepler-442 b
via Transit
If you liked this
Other systems in the same theme:
TRAPPIST-1
7 planets · 40.5 ly · M8.0 V
Seven Earth-sized planets around an ultracool dwarf — three in the habitable zone.
Proxima Centauri
2 planets · 4.2 ly · M5.5 V
Our nearest stellar neighbour hosts a potentially habitable terrestrial world.
Kepler-186
5 planets · 579.2 ly · M1
First Earth-sized planet found in another star's habitable zone (2014).
Experience it
See Kepler-442 in interactive 3D
Fly through the system, click any planet, watch orbits play out at 100× speed.
▶ Launch 3D scene