HD 128311 is 53.3 light-years from the Sun. The NASA Exoplanet Archive lists 2 planets around this K0 star; the first was found in 2002 by radial velocity (W. M. Keck Observatory).
Fly there in 3DHD 128311 c takes 921.5 days to go round its star once.
| Spectral type | K0 |
| Surface temperature | 4,965 K |
| Mass | 0.828 solar masses |
| Radius | 0.76 solar radii |
| Luminosity | 0.3079 times the Sun |
| Apparent magnitude | 7.48 |
| Age | about 0.96 billion years |
| Distance from the Sun | 53.3 light-years (16.3 parsecs) |
| Position (J2000) | RA 219.0032°, Dec 9.7454° |
| Constellation | Boötes |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| HD 128311 b | 453.0 days | 1.084 AU | 13.5 R⊕ estimated | 562.24 M⊕ minimum | Radial Velocity, 2002 |
| HD 128311 c | 921.5 days | 1.740 AU | 13 R⊕ estimated | 1204.3 M⊕ | Radial Velocity, 2005 |
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 4,965 K, 0.31 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 0.55 to 1.00 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 53 years ago, within living memory.