GJ 251 is 18.2 light-years from the Sun. The NASA Exoplanet Archive lists 2 planets around this M3.0 V star; the first was found in 2020 by radial velocity (W. M. Keck Observatory).
Fly there in 3DGJ 251 b goes round its star every 14.2 days, 6 times as often as Mercury goes round the Sun.
| Spectral type | M3.0 V |
| Surface temperature | 3,342 K |
| Mass | 0.35 solar masses |
| Radius | 0.36 solar radii |
| Luminosity | 0.0155 times the Sun |
| Apparent magnitude | 9.89 |
| Age | about 6.8 billion years |
| Distance from the Sun | 18.2 light-years (5.6 parsecs) |
| Position (J2000) | RA 103.7002°, Dec 33.2665° |
| Constellation | Gemini |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| GJ 251 b | 14.2 days | 0.0808 AU | 1.79 R⊕ estimated | 3.85 M⊕ minimum | Radial Velocity, 2020 |
| GJ 251 c | 53.6 days | 0.196 AU | 1.8 R⊕ estimated | 3.88 M⊕ minimum | Radial Velocity, 2025 |
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.