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Habitability
0/ 100
Uninhabitable

Niraeia

by Idk
0

Gas Giant

✦ Astra
Magnetic FieldExtreme Activity
Why is this a Gas Giant?Your planet has 86.0% hydrogen and helium, combined with a mass of 10.1x 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: 10.1x 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 (tidal flexing sustains geologic activity)
rotation10
Near tidally locked - one hemisphere perpetually scorched, other frozen, narrow habitable twilight zone only
Organic Chemistry84
Core organic elements (CHNO) present (tidal pools cycle wet and dry - a boost for prebiotic chemistry)
atmosphere12
Hydrogen-rich atmosphere typical of gas giants (partially stripped by slow rotation)
temperature0
Near absolute zero - all molecular activity ceases, impossible for life
magnetic Field100
Magnetic field provides radiation protection

Physical Properties

Mass
10.10x Earth (6.03e+25 kg)
Radius
2.16x Earth (13,772 km)
This planet: 2.16× Earth radiusEarth: 1× (baseline)
Surface Gravity
2.16x Earth (21.2 m/s²)
Surface Temperature
23 K (-250 °C / -419 °F)
Rotation Period
10.0 hours/day (faster than Earth)
This planet: 10 h/dayEarth: 24 h/day

Orbital Environment

Star Type
BH-type (Black Hole)
Distance from Star
3000.00 AU (449 billion km)
Orbital Period
51,962 years

Atmosphere

Hydrogen and helium dominated with trace methane and ammonia

Elemental Composition

H - Hydrogen
53.8%
He - Helium
32.3%
C - Carbon
5.4%

Surface Characteristics

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

Closest Real Exoplanet

K2-395 c74% similar
Orbiting K2-395
YoursK2-395 c
Mass10.1 × Earth11.4 × Earth
Radius3.50 × Earth3.40 × Earth
Density (composition)1.30 g/cm³1.60 g/cm³
Temperature22.8 K—
Starlight received0.00 × Earth—
Star temperature— 5,007 K
Matched on physical properties only — no confirmed exoplanet orbits a black hole.Discovered 2022 via transit · 936 light-years awaySource: NASA Exoplanet Archive
Moons
Moon 1rings0.010% - 1.8 radii

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

Moon 2stableOcean world0.010% - 4.1 radii

Small and distant: a quiet, stable companion.

Tidal braking locked the planet to its moon: one face forever moonward.

A thin tidal-warmed subsurface ocean may exist, but conditions are marginal (24/100).

Moon 3stableOcean world0.010% - 6.3 radii

Small and distant: a quiet, stable companion.

A thin tidal-warmed subsurface ocean may exist, but conditions are marginal (12/100).

Moon 4stable0.010% - 9.6 radii

Small and distant: a quiet, stable companion.

Moon 5stable0.010% - 14.6 radii

Small and distant: a quiet, stable companion.

Moon 6stable0.010% - 22.1 radii

Small and distant: a quiet, stable companion.

Moon 7stable0.010% - 33.7 radii

Small and distant: a quiet, stable companion.

Moon 8stable0.010% - 51.2 radii

Small and distant: a quiet, stable companion.

Moon 9stable0.010% - 77.9 radii

Small and distant: a quiet, stable companion.

+10 geology: tidal flexing sustains geologic activity+4 chemistry: tidal pools cycle wet and dry - a boost for prebiotic chemistry
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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