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Entering orbit…
Habitability
26/ 100
Extremely Harsh

GJ 667 C g

Ice WorldExtremely Harsh24 light years awayFound 2013

GJ 667 C g, from the NASA Exoplanet Archive (found 2013). Measured: 4.6 Earth masses, 0.549 AU, a 3350 K M-type star. Composition inferred from a measured bulk density of 0.58x Earth's — too light for bare rock, so a large fraction of water and ice, with an assumed 24-hour day — rotation cannot be measured for exoplanets.

Host star

GJ 667 C

Type
M-type (Red Dwarf)
Spectral type
M1.5 V
Temperature
3,350 K
Mass
0.33 ☉
Known planets
5, including this one
Luminosity
0.0137 ☉

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.

Ice World

Magnetic FieldLow Activity
Why is this a Ice World?Your planet orbits at 0.55 AU from its star, resulting in frigid temperatures of 138K.
Ice worlds form beyond the frost line where temperatures are low enough for water and other volatiles to freeze solid. They may have subsurface oceans beneath thick ice shells.
Classification Criteria:
✓ Distance: 0.55 AU (>3 AU) or Temperature <200K✓ Temperature: 138K✓ Water content: 50.0% for ice formation
Further reading
Imagined LifeJames Trefil & Michael SummersWhat could live on a world like this one: ice shells, supergravity, tidally locked twilight.Envisioning ExoplanetsMichael CarrollWhat these worlds might look like from the ground, painted from the same measurements this page renders.The Little Book of ExoplanetsJoshua WinnHow these worlds are found, and what a measurement can honestly tell us.Exoplanets: Diamond Worlds, Super Earths, Pulsar PlanetsMichael Summers & James TrefilThe strange end of the catalogue — carbon worlds, molten rock, planets orbiting dead stars.
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Habitability ScoreExtremely Harsh
26
Contributing Factors
temperature20
Very cold - water frozen, challenging for life
atmosphere70
Nitrogen atmosphere provides protection but not breathable
water22
Abundant water - frozen solid, no liquid phase at this temperature
magnetic Field100
Magnetic field provides radiation protection
geology60
Some geological activity provides slow nutrient cycling
Organic Chemistry80
Core organic elements (CHNO) present
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution

Physical Properties

Mass
4.60x Earth (2.75e+25 kg)
Radius
1.66x Earth (10,596 km)
This planet: 1.66× Earth radiusEarth: 1× (baseline)
Surface Gravity
1.66x Earth (16.3 m/s²)
Surface Temperature
138 K (-135 °C / -211 °F)
Rotation Period
24.0 hours/day
This planet: 24 h/dayEarth: 24 h/day

Orbital Environment

Star Type
M-type (Red Dwarf)
Distance from Star
0.55 AU (82.1 million km)
Orbital Period
271 days

Atmosphere

Thin nitrogen and methane atmosphere

Elemental Composition

O - Oxygen
41.2%
H - Hydrogen
17.6%
Si - Silicon
11.8%

Surface Characteristics

Frozen surface covered in water ice, possible subsurface ocean if tidal heating present
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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