Host star — Kepler-442
- Spectral type
- —
- Temperature
- 4,402 K
- Radius
- 0.60 R☉
- Mass
- 0.61 M☉
- Luminosity
- 0.117 L☉
- Distance
- 366.0 pc (1,194 ly)
Cooler than the Sun. Orange or red dwarf.
Kepler-442 b
Orbits Kepler-442 · 1,194 light-years from Earth
RockyTransit2015ESI 88 · Very Earth-like
Radius
1.34×
Earth
Mass
2.4×
Earth
Year
112d
Temp
241 K
-32°C
Gravity
1.3×
Earth
Distance
1,194
ly
What it would be like
Kepler-442 b is a rocky world, potentially similar in composition to Earth or Mars — a solid surface you could, in theory, stand on.
Surface gravity is about 1.3g — noticeably heavier what you're used to on Earth.
At -32°C, this world is cold — similar to Earth's polar regions or the surface of Mars. Water would likely be frozen, but subsurface liquid isn't ruled out.
An orbital period of 112 days makes the year 3.3× shorter than Earth's. You'd celebrate your birthday more often here.
Earth comparison
Logarithmic bars so Jupiter-class planets fit the same scale as Earth-size worlds.
Radius1.34R⊕
1/25×Earth = 125×
Mass2.36M⊕
1/10000×Earth = 110000×
Surface gravity1.31g
1/100×Earth = 1100×
Equilibrium temp241 K(-32°C)
0 KEarth 255 K2500 K
Side-by-side with Earth
Temperature in context
Liquid N₂Mars avgEarth eq.Earth sfc.Boiling H₂OVenus
Discovery & orbit
- Method
- Transit
- Year
- 2015
- Facility
- Kepler
- Semi-major axis
- 0.4090 AU
- Period
- 112.31 days
- Eccentricity
- 0.0400
- Density
- 5.39 g/cm³
Detected by measuring the tiny dip in starlight as the planet crosses in front of its star.
Mildly elliptical — similar to most Solar System planets.
Rocky composition likely. Earth is 5.51 g/cm³.
Discovered via · Transit
Tiny dip in starlight as the planet crosses in front of its star
A transit photometer watches a star nonstop and measures its brightness to ~0.01%. When a planet passes between us and the star, the star dims briefly — the deeper the dip, the bigger the planet. This is how Kepler and TESS found most known exoplanets.
- Overall share
- ~75% of all confirmed worlds
- Best for
- Earth-to-Neptune-sized planets on short orbits
Orbital Animation
Kepler-442Kepler-442 bOrbitEarth orbitHabitable zone
Drag to rotate · scroll to zoomSemi-major axis: 0.409 AUEccentricity: 0.0400Period: 112.3 days
Hertzsprung–Russell Diagram
Where this host star sits among … exoplanet host stars. The main sequence band runs diagonally — giants and supergiants sit above, white dwarfs below.
OBAFGKMCurrent star
How far is 1,194 light-years?
- A light beam leaving Earth right now would arrive in 1,194 years.
- At Voyager 1's speed (17 km/s), the trip would take approximately 21.0 million years.
- A radio signal sent today would arrive in 1193.6 years — and the reply wouldn't come back for twice that.
Earth Similarity Index
88/1000 — Nothing like Earth100 — Identical to Earth
ESI combines radius similarity and equilibrium temperature similarity. Earth = 100. Mars ≈ 73. Venus ≈ 44. This score reflects two physical parameters only — not atmosphere, water, or magnetic field.