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Entering orbit…
Habitability
25/ 100
Extremely Harsh

TRAPPIST-1 f

Ice WorldExtremely Harsh40 light years awayFound 2017

TRAPPIST-1 f, from the NASA Exoplanet Archive (found 2017). Measured: 1.04 Earth masses, 0.0385 AU, a 2566 K M-type star. Composition inferred from a measured bulk density of 0.92x Earth's, which is rock and iron, with a day locked to its 9.2-day year, as anything orbiting this close would be.

Host star

TRAPPIST-1

Type
M-type (Red Dwarf)
Spectral type
M8.0 V
Temperature
2,566 K
Radius
0.119 ☉
Mass
0.0898 ☉
Known planets
7, including this one
Luminosity
5.53e-4 ☉

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

Low Activity
Why is this a Ice World?Your planet orbits at 0.04 AU from its star, resulting in frigid temperatures of 220K.
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: 0.04 AU (>3 AU) or Temperature <200K✓ Temperature: 220K✓ Water content: 34.4% 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
25
Contributing Factors
temperature40
Extreme temperature - very difficult for life
atmosphere42
Nitrogen atmosphere provides protection but not breathable (partially stripped by slow rotation)
water28
Limited water content - frozen solid, no liquid phase at this temperature
magnetic Field30
No magnetic field - vulnerable to solar radiation
geology60
Some geological activity provides slow nutrient cycling
Organic Chemistry80
Core organic elements (CHNO) present
rotation30
Very slow rotation - severe temperature swings between eternal day and night sides

Physical Properties

Mass
1.04x Earth (6.21e+24 kg)
Radius
1.01x Earth (6,455 km)
This planet: 1.01× Earth radiusEarth: 1× (baseline)
Surface Gravity
1.01x Earth (9.9 m/s²)
Surface Temperature
220 K (-53 °C / -63 °F)
Rotation Period
221.0 hours/day (slower than Earth)
This planet: 221 h/dayEarth: 24 h/day

Orbital Environment

Star Type
M-type (Red Dwarf)
Distance from Star
0.04 AU (5.76 million km)
Orbital Period
5 days

Atmosphere

Thin nitrogen and methane atmosphere

Elemental Composition

O - Oxygen
31.3%
Si - Silicon
25.0%
Fe - Iron
12.5%

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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