HIP 5158 b
Gas GiantUninhabitable168 light years awayFound 2009
HIP 5158 b, from the NASA Exoplanet Archive (found 2009). Measured: 451 Earth masses, 0.89 AU, a 4962 K K-type star. Composition inferred from a mass of 451 Earths, which is giant territory whatever its 0.18x density suggests, with an assumed 24-hour day — rotation cannot be measured for exoplanets.
HIP 5158
- Type
- K-type (Orange)
- Temperature
- 4,962 K
- Radius
- 0.75 ☉
- Mass
- 0.78 ☉
- Known planets
- 2, including this one
- Luminosity
- 0.110 ☉
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 451.0x 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: 86.0% (>60% required)✓ Mass: 451.0x Earth (>10x required)
Habitability ScoreUninhabitable
Contributing Factors
temperature20
Very cold - water frozen, challenging for 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 Chemistry80
Core organic elements (CHNO) present
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Physical Properties
Mass
451.00x Earth (2.69e+27 kg)Radius
7.67x Earth (48,858 km)Surface Gravity
7.67x Earth (75.2 m/s²)Surface Temperature
170 K (-103 °C / -153 °F)Rotation Period
24.0 hours/dayOrbital Environment
Star Type
K-type (Orange)Distance from Star
0.89 AU (133 million km)Orbital Period
1.00 yearsAtmosphere
Hydrogen and helium dominated with trace methane and ammonia
Elemental Composition
H - Hydrogen
53.8%
He - Helium
32.3%
O - Oxygen
5.4%



