K2-89 b
Lava WorldUninhabitable280 light years awayFound 2016
K2-89 b, from the NASA Exoplanet Archive (found 2016). Measured: 0.17 Earth masses, 0.0146 AU, a 3691 K M-type star. Composition inferred from a measured bulk density of 0.73x Earth's, which is rock and iron, with a day locked to its 1.1-day year, as anything orbiting this close would be. Note: TerraForge comes out at 1072 K against the archive's 830 K, because it models stars by spectral class, and K2-89 is not an average M-type.
K2-89
- Type
- M-type (Red Dwarf)
- Temperature
- 3,691 K
- Radius
- 0.318 ☉
- Mass
- 0.347 ☉
- Known planets
- 1 (this one)
- Luminosity
- 0.0471 ☉
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.
Lava World
Extreme Activity
Why is this a Lava World?Your planet's proximity to its star (0.01 AU) results in extreme surface temperatures of 1072K.
Lava worlds orbit so close to their stars that rocky surfaces melt into oceans of molten rock. Recent planet formation can also create temporary lava worlds.
Classification Criteria:
✓ Temperature: 1072K (>1000K)
Habitability ScoreUninhabitable
Contributing Factors
temperature0
Inferno world - temperatures exceed all possibility of life
atmosphere10
No atmosphere - exposed to radiation and temperature extremes
water8
Limited water content - boiling away, little would be retained
magnetic Field30
No magnetic field - vulnerable to solar radiation
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
0.17x Earth (1.02e+24 kg)Radius
0.55x Earth (3,529 km)Surface Gravity
0.55x Earth (5.4 m/s²)Surface Temperature
1,072 K (799 °C / 1,470 °F)Rotation Period
26.4 hours/day (slower than Earth)Orbital Environment
Star Type
M-type (Red Dwarf)Distance from Star
0.01 AU (2.18 million km)Orbital Period
1 dayTime Dilation
Clocks run 9.6 seconds per year slower than deep space — about 13 minutes over a lifetimeAtmosphere
Minimal - too hot to retain
Elemental Composition
O - Oxygen
31.3%
Si - Silicon
25.0%
Fe - Iron
12.5%



