TOI-700 b
Rocky TerrestrialUninhabitable101 light years awayFound 2020
TOI-700 b, from the NASA Exoplanet Archive (found 2020). Measured: 0.704 Earth masses, 0.0677 AU, a 3459 K M-type star. Composition inferred from a measured bulk density of 0.92x Earth's, which is rock and iron, with a day locked to its 10.0-day year, as anything orbiting this close would be.
TOI-700
- Type
- M-type (Red Dwarf)
- Spectral type
- M2.5 V
- Temperature
- 3,459 K
- Radius
- 0.421 ☉
- Mass
- 0.415 ☉
- Known planets
- 4, including this one
- Luminosity
- 0.0229 ☉
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
Low 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: 0.7x Earth (terrestrial range)
Habitability ScoreUninhabitable
Contributing Factors
temperature15
Extremely hot - hostile to known life forms
atmosphere42
Nitrogen atmosphere provides protection but not breathable (partially stripped by slow rotation)
water41
Limited water content - likely as steam
magnetic Field30
No magnetic field - vulnerable to solar radiation
geology60
Some geological activity provides slow nutrient cycling
Organic Chemistry80
Core organic elements (CHNO) present
rotation30
Very slow rotation - extreme temperature swings between eternal day and night sides
Physical Properties
Mass
0.70x Earth (4.20e+24 kg)Radius
0.89x Earth (5,668 km)Surface Gravity
0.89x Earth (8.7 m/s²)Surface Temperature
421 K (148 °C / 298 °F)Rotation Period
239.5 hours/day (slower than Earth)Orbital Environment
Star Type
M-type (Red Dwarf)Distance from Star
0.07 AU (10.1 million km)Orbital Period
12 daysAtmosphere
Thin CO₂ and nitrogen atmosphere
Elemental Composition
O - Oxygen
31.3%
Si - Silicon
25.0%
Fe - Iron
12.5%



