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Entering orbit…
Habitability
40/ 100
Marginal

HILT-9899 b

0

Gas Giant

Magnetic FieldExtreme Activity
Why is this a Gas Giant?Your planet has 0.0% hydrogen and helium, combined with a mass of 8.3x 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: 0.0% (>60% required)✓ Mass: 8.3x Earth (>10x required)
Habitability ScoreMarginal
40
Contributing Factors
water15
No solid surface — any water is locked in a supercritical mantle and hot ice, not oceans
geology40
Extreme volcanic activity may be hazardous
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Organic Chemistry0
Limited organic chemistry potential - chlorine-laced environment attacks organic molecules
atmosphere30
Hydrogen-rich atmosphere typical of gas giants
temperature40
Extreme temperature - very difficult for life
magnetic Field100
Magnetic field provides radiation protection

Physical Properties

Mass
8.30x Earth (4.96e+25 kg)
Radius
2.02x Earth (12,899 km)
This planet: 2.02× Earth radiusEarth: 1× (baseline)
Surface Gravity
2.02x Earth (19.9 m/s²)
Surface Temperature
223 K (-51 °C / -59 °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
1.56 AU (233 million km)
Orbital Period
1.95 years

Atmosphere

Hydrogen and helium dominated with trace methane and ammonia

Elemental Composition

Cl - Chlorine
100.0%

Surface Characteristics

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

Closest Real Exoplanet

Kepler-1600 b90% similar
Orbiting Kepler-1600
YoursKepler-1600 b
Mass8.30 × Earth9.96 × Earth
Radius3.28 × Earth3.13 × Earth
Density (composition)1.30 g/cm³1.79 g/cm³
Temperature222.6 K209.0 K
Starlight received0.41 × Earth0.40 × Earth
Star temperature5,600 K5,214 K
Discovered 2016 via transit · 3,359 light-years awaySource: NASA Exoplanet Archive
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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