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Entering orbit…
Habitability
0/ 100
Uninhabitable

Athína

by Polemos
0

Gas Giant

Ílios
Magnetic FieldExtreme Activity
Why is this a Gas Giant?Your planet has 65.0% hydrogen and helium, combined with a mass of 15.0x 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: 65.0% (>60% required)✓ Mass: 15.0x Earth (>10x required)
Habitability ScoreUninhabitable
0
Contributing Factors
water15
No solid surface — any water is locked in a supercritical mantle and hot ice, not oceans
geology50
Extreme volcanic activity may be hazardous (impact-resurfaced crust)
rotation30
Very slow rotation - extreme temperature swings between eternal day and night sides
Organic Chemistry84
Core organic elements (CHNO) present (tidal pools cycle wet and dry - a boost for prebiotic chemistry)
atmosphere28
Hydrogen-rich atmosphere typical of gas giants (atmosphere partially stripped by the moon impact)
temperature0
Extremely hot - hostile to known life forms (surface remelted by the moon impact - molten regardless of orbit)
magnetic Field100
Magnetic field provides radiation protection

Physical Properties

Mass
15.00x Earth (8.96e+25 kg)
Radius
2.47x Earth (15,712 km)
This planet: 2.47× Earth radiusEarth: 1× (baseline)
Surface Gravity
2.47x Earth (24.2 m/s²)
Surface Temperature
580 K (306 °C / 584 °F)
Rotation Period
83.0 hours/day (slower than Earth)
This planet: 83 h/dayEarth: 24 h/day

Orbital Environment

Star Type
K-type (Orange)
Distance from Star
0.33 AU (49.4 million km)
Orbital Period
83 days

Atmosphere

Hydrogen and helium dominated with trace methane and ammonia

Elemental Composition

H - Hydrogen
40.0%
He - Helium
25.0%
C - Carbon
15.0%

Surface Characteristics

No solid surface - thick gaseous envelope with possible rocky core deep within

Closest Real Exoplanet

HD 51608 c89% similar
Orbiting HD 51608
YoursHD 51608 c
Mass15.0 × Earth14.3 × Earth
Radius3.99 × Earth3.87 × Earth
Density (composition)1.30 g/cm³1.36 g/cm³
Temperature579.6 K401.0 K
Starlight received3.67 × Earth3.93 × Earth
Star temperature4,450 K5,358 K
Discovered 2019 via radial velocity · 114 light-years awaySource: NASA Exoplanet Archive
Moons
Moon 1rings0.071% - 2.8 radii

Inside the synchronous orbit: it spiraled inward and was torn apart at the Roche limit (Phobos's fate).

Moon 2merged0.063% - 6.9 radii

Merged with an adjacent moon: too close for both to hold a stable orbit.

Moon 3crashed0.056% - 5.9 radii

Inside the synchronous orbit: tidal decay dragged it down - it struck the planet ages ago.

Moon 4rings0.056% - 9.7 radii

Inside the synchronous orbit: it spiraled inward and was torn apart at the Roche limit (Phobos's fate).

Moon 5receding0.050% - 15.4 radii

Outside the synchronous orbit: slowly receding, like Luna (~cm per year).

Moon 6receding0.050% - 26.1 radii

Outside the synchronous orbit: slowly receding, like Luna (~cm per year).

+4 chemistry: tidal pools cycle wet and dry - a boost for prebiotic chemistry-2 atmosphere: atmosphere partially stripped by the moon impact+10 geology: impact-resurfaced crust-85 temperature: surface remelted by the moon impact - molten regardless of orbit
Surface views from three worlds: rocky ground under a ringed sky, a cloud deck, and a lit desert

New: Stand on Your World 🏔️

Every planet you build can now be seen from the ground. The terrain, the color of the sky, the weather and what hangs overhead are all read from the same numbers that shape the globe — so a thin-aired world gives you sunlit rock under a near-black sky crowded with stars, a runaway greenhouse seals you under an unbroken sulfur lid, and a gas giant leaves you in the cloud tops with nothing solid beneath you at all. If one of your moons wandered inside the Roche limit, what is left of it arcs overhead as rings.

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