HATS-38 b
Gas GiantUninhabitable1121 light years awayFound 2020
HATS-38 b, from the NASA Exoplanet Archive (found 2020). Measured: 23.5 Earth masses, 0.0504 AU, a 5732 K G-type star. Composition inferred from a measured bulk density of 0.07x Earth's, which only hydrogen and helium can explain, with a day locked to its 4.4-day year, as anything orbiting this close would be.
HATS-38
- Type
- G-type (Yellow (Sun-like))
- Temperature
- 5,732 K
- Radius
- 1.1 ☉
- Mass
- 0.89 ☉
- Known planets
- 1 (this one)
- Luminosity
- 1.18 ☉
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 23.5x 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: 23.5x 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 Chemistry80
Core organic elements (CHNO) present
rotation30
Very slow rotation - extreme temperature swings between eternal day and night sides
Physical Properties
Mass
23.50x Earth (1.40e+26 kg)Radius
2.86x Earth (18,249 km)Surface Gravity
2.86x Earth (28.1 m/s²)Surface Temperature
1,293 K (1,020 °C / 1,868 °F)Rotation Period
105.1 hours/day (slower than Earth)Orbital Environment
Star Type
G-type (Yellow (Sun-like))Distance from Star
0.05 AU (7.54 million km)Orbital Period
4 daysTime Dilation
Clocks run 9.3 seconds per year slower than deep space — about 12 minutes over a lifetimeAtmosphere
Hydrogen and helium dominated with trace methane and ammonia
Elemental Composition
H - Hydrogen
53.8%
He - Helium
32.3%
O - Oxygen
5.4%



