TOI-771 b
Rocky TerrestrialExtremely Harsh82 light years awayFound 2024
TOI-771 b, from the NASA Exoplanet Archive (found 2024). Measured: 2.47 Earth masses, 0.0208 AU, a 3370 K M-type star. Composition inferred from a measured bulk density of 0.98x Earth's, which is rock and iron, with a day locked to its 2.3-day year, as anything orbiting this close would be.
TOI-771
- Type
- M-type (Red Dwarf)
- Spectral type
- M3
- Temperature
- 3,370 K
- Radius
- 0.232 ☉
- Mass
- 0.22 ☉
- Known planets
- 2, including this one
- Luminosity
- 6.26e-3 ☉
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 FieldHigh 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: 2.5x Earth (terrestrial range)
Habitability ScoreExtremely Harsh
Contributing Factors
temperature15
Extremely hot - hostile to known life forms
atmosphere70
Nitrogen atmosphere provides protection but not breathable
water17
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
rotation65
Slow rotation - significant day/night temperature variations, but life can adapt
Physical Properties
Mass
2.47x Earth (1.48e+25 kg)Radius
1.35x Earth (8,612 km)Surface Gravity
1.35x Earth (13.3 m/s²)Surface Temperature
550 K (277 °C / 531 °F)Rotation Period
55.9 hours/day (slower than Earth)Orbital Environment
Star Type
M-type (Red Dwarf)Distance from Star
0.02 AU (3.11 million km)Orbital Period
2 daysTime Dilation
Clocks run 6.7 seconds per year slower than deep space — about 9 minutes over a lifetimeAtmosphere
Thin CO₂ and nitrogen atmosphere
Elemental Composition
O - Oxygen
31.3%
Si - Silicon
25.0%
Fe - Iron
12.5%



