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Entering orbit…
Habitability
69/ 100
Habitable

HD 20794 e

BarrenHabitable20 light years awayFound 2017

HD 20794 e, from the NASA Exoplanet Archive (found 2017). Measured: 4.77 Earth masses, 0.509 AU, a 5401 K G-type star. Composition inferred from a measured bulk density of 0.57x 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

HD 20794

Type
G-type (Yellow (Sun-like))
Spectral type
G8
Temperature
5,401 K
Radius
0.93 ☉
Mass
0.813 ☉
Known planets
4, including this one
Luminosity
0.687 ☉

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.

Barren

Magnetic FieldHigh Activity
Why is this a Barren?Your planet has an unusual composition that doesn't fit standard classifications, or lacks the elements needed for complex geological processes.
Barren worlds can form from uncommon element combinations or may be remnants of larger bodies that lost their atmospheres and volatile materials.
Classification Criteria:
Composition doesn't match standard planet typesMass: 4.8x EarthTemperature: 382K
Further reading
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.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 ScoreHabitable
69
Contributing Factors
temperature40
Extreme temperature - very difficult for life
atmosphere70
Nitrogen atmosphere provides protection but not breathable
water97
Abundant water - likely as steam
magnetic Field100
Magnetic field provides radiation protection
geology90
Active geology recycles nutrients and drives carbon cycle
Organic Chemistry80
Core organic elements (CHNO) present
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution

Physical Properties

Mass
4.77x Earth (2.85e+25 kg)
Radius
1.68x Earth (10,725 km)
This planet: 1.68× Earth radiusEarth: 1× (baseline)
Surface Gravity
1.68x Earth (16.5 m/s²)
Surface Temperature
382 K (109 °C / 227 °F)
Rotation Period
24.0 hours/day
This planet: 24 h/dayEarth: 24 h/day

Orbital Environment

Star Type
G-type (Yellow (Sun-like))
Distance from Star
0.51 AU (76.1 million km)
Orbital Period
133 days

Atmosphere

Thin CO₂ and nitrogen atmosphere

Elemental Composition

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

Surface Characteristics

Barren rocky surface with unusual elemental composition
The TerraForge exoplanet catalog: 5,572 real exoplanets run through the simulation, with a search field and rendered worlds grouped by type

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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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