GJ 581 is 20.5 light-years from the Sun. The NASA Exoplanet Archive lists 3 planets around this M3.0 V star; the first was found in 2005 by radial velocity (La Silla Observatory).
Fly there in 3DGJ 581 e goes round its star every 3.15 days, 28 times as often as Mercury goes round the Sun.
| Spectral type | M3.0 V |
| Surface temperature | 3,500 K |
| Mass | 0.295 solar masses |
| Radius | 0.302 solar radii |
| Luminosity | 0.01236 times the Sun |
| Apparent magnitude | 10.57 |
| Age | about 4.3 billion years |
| Distance from the Sun | 20.5 light-years (6.3 parsecs) |
| Position (J2000) | RA 229.8565°, Dec -7.7227° |
| Constellation | Libra |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| GJ 581 e | 3.15 days | 0.0280 AU | 1.38 R⊕ estimated | 2.48 M⊕ | Radial Velocity, 2009 |
| GJ 581 b | 5.37 days | 0.0399 AU | 4.79 R⊕ estimated | 20.5 M⊕ | Radial Velocity, 2005 |
| GJ 581 c | 12.9 days | 0.0718 AU | 2.5 R⊕ estimated | 6.81 M⊕ | Radial Velocity, 2007 |
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 3,500 K, 0.012 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 0.12 to 0.22 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 21 years ago, within living memory.