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Entering orbit…
Habitability
0/ 100
Uninhabitable

K2-137 b

Gas GiantUninhabitable322 light years awayFound 2017

K2-137 b, from the NASA Exoplanet Archive (found 2017). Measured: 159 Earth masses, 0.0058 AU, a 3697 K M-type star. Composition inferred from a mass of 159 Earths, which is giant territory whatever its 606.54x density suggests, with a day locked to its 0.2-day year, as anything orbiting this close would be.

Host star

K2-137

Type
M-type (Red Dwarf)
Spectral type
M3 V
Temperature
3,697 K
Radius
0.29 ☉
Mass
0.463 ☉
Known planets
1 (this one)
Luminosity
0.0328 ☉

Published by the NASA Exoplanet Archive. This world’s temperature and habitability score are computed from this star’s measured luminosity, not from a stand-in for its class.

Gas Giant

Magnetic FieldExtreme Activity
Why is this a Gas Giant?Your planet has 86.0% hydrogen and helium, combined with a mass of 159.0x Earth, which exceeds the gas giant threshold.
Gas giants form when massive cores capture enormous atmospheres of light gases. They typically form beyond the 'frost line' where volatiles can condense.
Classification Criteria:
✓ Hydrogen + Helium: 86.0% (>60% required)✓ Mass: 159.0x Earth (>10x required)
Further reading
Exoplanets: Diamond Worlds, Super Earths, Pulsar PlanetsMichael Summers & James TrefilThe strange end of the catalogue — carbon worlds, molten rock, planets orbiting dead stars.The Little Book of ExoplanetsJoshua WinnHow these worlds are found, and what a measurement can honestly tell us.Envisioning ExoplanetsMichael CarrollWhat these worlds might look like from the ground, painted from the same measurements this page renders.Imagined LifeJames Trefil & Michael SummersWhat could live on a world like this one: ice shells, supergravity, tidally locked twilight.
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Habitability ScoreUninhabitable
0
Contributing Factors
temperature0
Inferno world - temperatures exceed all possibility of life
atmosphere30
Hydrogen-rich atmosphere typical of gas giants
water15
No solid surface — any water is locked in a supercritical mantle and hot ice, not oceans
magnetic Field100
Magnetic field provides radiation protection
geology40
Extreme volcanic activity may be hazardous
Organic Chemistry80
Core organic elements (CHNO) present
rotation25
Very fast rotation - perpetual hurricane-force winds, extreme Coriolis effects, hazardous for complex life

Physical Properties

Mass
159.00x Earth (9.50e+26 kg)
Radius
5.42x Earth (34,515 km)
This planet: 5.42× Earth radiusEarth: 1× (baseline)
Surface Gravity
5.42x Earth (53.1 m/s²)
Surface Temperature
1,186 K (912 °C / 1,674 °F)
Rotation Period
4.3 hours/day (faster than Earth)
This planet: 4 h/dayEarth: 24 h/day

Orbital Environment

Star Type
M-type (Red Dwarf)
Distance from Star
0.01 AU (1.5 million km)
Orbital Period
1 day
Time Dilation
Clocks run 14.0 seconds per year slower than deep space — about 19 minutes over a lifetime

Atmosphere

Hydrogen and helium dominated with trace methane and ammonia

Elemental Composition

H - Hydrogen
53.8%
He - Helium
32.3%
O - Oxygen
5.4%

Surface Characteristics

No solid surface - thick gaseous envelope with possible rocky core deep within
The TerraForge exoplanet catalog: 5,572 real exoplanets run through the simulation, with a search field and rendered worlds grouped by type

New: The Exoplanet Catalog 🔭

Every confirmed planet NASA has measured well enough to build — 5,572 of them — is now in here, and none of them arrived with a label. Their real mass, radius, orbit and star go through the same simulation that runs everything you make, and it decides what each one is: gas giant, lava world, ocean, ice. Sixteen come out Earth-like. Find TRAPPIST-1e, stand on its surface, and see what a red dwarf's light actually looks like from the ground.

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