TOI-2120 is 105 light-years from the Sun. The NASA Exoplanet Archive lists 1 planet around this 3,131 K star; the first was found in 2024 by transit (Transiting Exoplanet Survey Satellite (TESS)).
Fly there in 3DTOI-2120 b goes round its star every 5.80 days, 15 times as often as Mercury goes round the Sun.
| Surface temperature | 3,131 K |
| Mass | 0.211 solar masses |
| Radius | 0.245 solar radii |
| Luminosity | 0.00517 times the Sun |
| Apparent magnitude | 15.648 |
| Distance from the Sun | 104.9 light-years (32.2 parsecs) |
| Position (J2000) | RA 23.5073°, Dec 65.5140° |
| Constellation | Cassiopeia |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| TOI-2120 b | 5.80 days | 0.0377 AU | 2.122 R⊕ | 6.8 M⊕ | Transit, 2024 |
Values are the NASA Exoplanet Archive’s composite parameters. A radius marked estimated comes from a mass–radius relation; a mass marked minimum is M sin i. Planet sizes and colours in the 3D view are renderings: none of these worlds has been photographed as more than a point of light.
For a star of 3,131 K, 0.0052 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 0.075 to 0.15 AU. None of its known planets orbits inside it. The zone says how much starlight arrives, not whether a planet has water or air. The edges follow Kopparapu et al. (2014), as the 3D view draws them.
The light you see left 105 years ago, around 1920.