HD 177830 is 205 light-years from the Sun. The NASA Exoplanet Archive lists 2 planets around this K0 star; the first was found in 1999 by radial velocity (W. M. Keck Observatory).
Fly there in 3DHD 177830 b takes 410.1 days to go round its star once.
HD 177830 is one of 2 stars in its system: the other is drawn where the Washington Double Star Catalog measures it on the sky.
| Spectral type | K0 |
| Surface temperature | 4,901 K |
| Mass | 1.7 solar masses |
| Radius | 3.26 solar radii |
| Luminosity | 4.842 times the Sun |
| Apparent magnitude | 7.18 |
| Age | about 4.4 billion years |
| Distance from the Sun | 204.7 light-years (62.8 parsecs) |
| Position (J2000) | RA 286.3364°, Dec 25.9204° |
| Constellation | Lyra |
HD 177830 B is a M4V star of magnitude 15, judged a true companion. In 2014 it was 1.7″ from HD 177830, at position angle 85° (Washington Double Star Catalog, 19053+2555 EGN 24 AB): 107 AU on the sky at this distance. The true distance can only be larger.
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| HD 177830 c | 110.9 days | 0.514 AU | 7.87 R⊕ estimated | 47.672 M⊕ minimum | Radial Velocity, 2010 |
| HD 177830 b | 410.1 days | 1.140 AU | 13.5 R⊕ estimated | 537.13 M⊕ minimum | Radial Velocity, 1999 |
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 4,901 K, 4.8 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 2.19 to 3.98 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 205 years ago, around 1820.