GJ 806 b
Rocky TerrestrialUninhabitable39 light years awayFound 2023
GJ 806 b, from the NASA Exoplanet Archive (found 2023). Measured: 1.9 Earth masses, 0.0141 AU, a 3600 K M-type star. Composition inferred from a measured bulk density of 0.81x Earth's, which is rock and iron, with a day locked to its 0.9-day year, as anything orbiting this close would be.
GJ 806
- Type
- M-type (Red Dwarf)
- Spectral type
- M1.5 V
- Temperature
- 3,600 K
- Radius
- 0.414 ☉
- Mass
- 0.413 ☉
- Known planets
- 2, including this one
- Luminosity
- 0.0260 ☉
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.
Rocky Terrestrial
Magnetic FieldModerate Activity
Why is this a Rocky Terrestrial?Your planet is dominated by silicate (25.0%) and iron (12.5%) content, forming a rocky terrestrial body.
Rocky terrestrial planets are primarily composed of silicate rocks and metals. They're the most common type of small planet in the universe.
Classification Criteria:
✓ Silicon: 25.0% + Iron: 12.5% + Magnesium: 3.8%✓ Mass: 1.9x Earth (terrestrial range)
Habitability ScoreUninhabitable
Contributing Factors
temperature5
Scorching - hot enough to melt lead, though rock stays solid; no chance for life
atmosphere70
Nitrogen atmosphere provides protection but not breathable
water8
Limited water content - boiling away, little would be retained
magnetic Field100
Magnetic field provides radiation protection
geology90
Active geology recycles nutrients and drives carbon cycle
Organic Chemistry80
Core organic elements (CHNO) present
rotation100
Optimal rotation period - balanced day/night cycle, moderate weather, and good heat distribution
Physical Properties
Mass
1.90x Earth (1.13e+25 kg)Radius
1.24x Earth (7,891 km)Surface Gravity
1.24x Earth (12.2 m/s²)Surface Temperature
954 K (681 °C / 1,257 °F)Rotation Period
22.2 hours/day (faster than Earth)Orbital Environment
Star Type
M-type (Red Dwarf)Distance from Star
0.01 AU (2.11 million km)Orbital Period
1 dayTime Dilation
Clocks run 9.9 seconds per year slower than deep space — about 13 minutes over a lifetimeAtmosphere
Thin CO₂ and nitrogen atmosphere
Elemental Composition
O - Oxygen
31.3%
Si - Silicon
25.0%
Fe - Iron
12.5%



