HD 213885 b
Gas GiantUninhabitable157 light years awayFound 2019
HD 213885 b, from the NASA Exoplanet Archive (found 2019). Measured: 8.83 Earth masses, 0.0201 AU, a 5978 K G-type star. Composition inferred from a measured bulk density of 1.65x Earth's, far too high for silicates alone — an iron-rich world, with a day locked to its 1.0-day year, as anything orbiting this close would be.
HD 213885
- Type
- G-type (Yellow (Sun-like))
- Spectral type
- G
- Temperature
- 5,978 K
- Radius
- 1.1 ☉
- Mass
- 1.07 ☉
- Known planets
- 2, including this one
- Luminosity
- 1.38 ☉
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 0.0% hydrogen and helium, combined with a mass of 8.8x 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: 8.8x Earth (>10x required)
Habitability ScoreUninhabitable
Contributing Factors
temperature0
Inferno world - temperatures exceed all possibility of life
atmosphere30
Hydrogen-rich atmosphere typical of gas giants
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 Chemistry20
Limited organic chemistry potential
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Physical Properties
Mass
8.83x Earth (5.27e+25 kg)Radius
2.07x Earth (13,168 km)Surface Gravity
2.07x Earth (20.3 m/s²)Surface Temperature
2,125 K (1,852 °C / 3,366 °F)Rotation Period
24.2 hours/day (slower than Earth)Orbital Environment
Star Type
G-type (Yellow (Sun-like))Distance from Star
0.02 AU (3.01 million km)Orbital Period
1 dayTime Dilation
Clocks run 23.3 seconds per year slower than deep space — about 31 minutes over a lifetimeAtmosphere
Hydrogen and helium dominated with trace methane and ammonia
Elemental Composition
Si - Silicon
36.6%
Fe - Iron
24.4%
Mg - Magnesium
12.2%



