LTT 9779 b
Ice GiantUninhabitable262 light years awayFound 2020
LTT 9779 b, from the NASA Exoplanet Archive (found 2020). Measured: 29.3 Earth masses, 0.0168 AU, a 5443 K G-type star. Composition inferred from a measured bulk density of 0.28x Earth's — too light for bare rock, so a large fraction of water and ice, with a day locked to its 0.8-day year, as anything orbiting this close would be.
LTT 9779
- Type
- G-type (Yellow (Sun-like))
- Spectral type
- G7 V
- Temperature
- 5,443 K
- Radius
- 0.949 ☉
- Mass
- 1.02 ☉
- Known planets
- 1 (this one)
- Luminosity
- 0.680 ☉
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.
Ice Giant
Magnetic FieldExtreme Activity
Why is this a Ice Giant?Your planet has moderate mass (29.3x Earth) with significant water, carbon, and nitrogen content, characteristic of ice giants.
Ice giants like Uranus and Neptune have icy interiors with thick atmospheres of hydrogen and helium, but not enough to be classified as gas giants.
Classification Criteria:
✓ Mass: 29.3x Earth (5-20x range)✓ Water/Carbon/Nitrogen rich composition
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
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Physical Properties
Mass
29.30x Earth (1.75e+26 kg)Radius
3.08x Earth (19,641 km)Surface Gravity
3.08x Earth (30.2 m/s²)Surface Temperature
1,948 K (1,675 °C / 3,046 °F)Rotation Period
19.0 hours/day (faster than Earth)Orbital Environment
Star Type
G-type (Yellow (Sun-like))Distance from Star
0.02 AU (2.51 million km)Orbital Period
1 dayTime Dilation
Clocks run 27.8 seconds per year slower than deep space — about 37 minutes over a lifetimeAtmosphere
Hydrogen and helium with water, methane, and ammonia ices
Elemental Composition
O - Oxygen
41.2%
H - Hydrogen
17.6%
Si - Silicon
11.8%



