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Entering orbit…
Habitability
0/ 100
Uninhabitable

HD 105618 b

Gas GiantUninhabitable229 light years awayFound 2022

HD 105618 b, from the NASA Exoplanet Archive (found 2022). Measured: 25.4 Earth masses, 0.091 AU, a 5671 K G-type star. Composition inferred from a measured bulk density of 0.16x Earth's, which only hydrogen and helium can explain, with a day locked to its 10.0-day year, as anything orbiting this close would be.

Host star

HD 105618

Type
G-type (Yellow (Sun-like))
Temperature
5,671 K
Radius
1.27 ☉
Mass
1.01 ☉
Known planets
2, including this one
Luminosity
1.51 ☉

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 25.4x 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: 25.4x 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
atmosphere18
Hydrogen-rich atmosphere typical of gas giants (partially stripped by slow rotation)
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
rotation30
Very slow rotation - extreme temperature swings between eternal day and night sides

Physical Properties

Mass
25.40x Earth (1.52e+26 kg)
Radius
2.94x Earth (18,728 km)
This planet: 2.94× Earth radiusEarth: 1× (baseline)
Surface Gravity
2.94x Earth (28.8 m/s²)
Surface Temperature
1,024 K (751 °C / 1,384 °F)
Rotation Period
240.0 hours/day (slower than Earth)
This planet: 240 h/dayEarth: 24 h/day

Orbital Environment

Star Type
G-type (Yellow (Sun-like))
Distance from Star
0.09 AU (13.6 million km)
Orbital Period
10 days
Time Dilation
Clocks run 5.1 seconds per year slower than deep space — about 7 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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