HD 5388 b
Gas GiantExtremely Harsh173 light years awayFound 2010
HD 5388 b, from the NASA Exoplanet Archive (found 2010). Measured: 1020 Earth masses, 1.76 AU, a 6297 K F-type star. Composition inferred from a mass of 1020 Earths, which is giant territory whatever its 0.45x density suggests, with an assumed 24-hour day — rotation cannot be measured for exoplanets.
HD 5388
- Type
- F-type (White)
- Spectral type
- F6 V
- Temperature
- 6,297 K
- Radius
- 1.91 ☉
- Mass
- 1.21 ☉
- Known planets
- 1 (this one)
- Luminosity
- 4.60 ☉
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 1020.0x 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: 1020.0x Earth (>10x required)
Habitability ScoreExtremely Harsh
Contributing Factors
temperature100
Optimal temperature range for liquid water and 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
1020.00x Earth (6.09e+27 kg)Radius
10.07x Earth (64,132 km)Surface Gravity
10.07x Earth (98.7 m/s²)Surface Temperature
308 K (34 °C / 94 °F)Rotation Period
24.0 hours/dayOrbital Environment
Star Type
F-type (White)Distance from Star
1.76 AU (263 million km)Orbital Period
2.05 yearsAtmosphere
Hydrogen and helium dominated with trace methane and ammonia
Elemental Composition
H - Hydrogen
53.8%
He - Helium
32.3%
O - Oxygen
5.4%



