HD 40307 is 42.2 light-years from the Sun. The NASA Exoplanet Archive lists 5 planets around this K2.5 V star; the first was found in 2009 by radial velocity (La Silla Observatory).
Fly there in 3DHD 40307 b goes round its star every 4.31 days, 20 times as often as Mercury goes round the Sun.
| Spectral type | K2.5 V |
| Surface temperature | 4,956 K |
| Mass | 0.77 solar masses |
| Radius | 0.716684 solar radii |
| Luminosity | 0.2296 times the Sun |
| Apparent magnitude | 7.17 |
| Age | about 4.5 billion years |
| Distance from the Sun | 42.2 light-years (12.9 parsecs) |
| Position (J2000) | RA 88.5172°, Dec -60.0237° |
| Constellation | Pictor |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| HD 40307 b | 4.31 days | 0.0468 AU | — | 1189 M⊕ | Radial Velocity, 2009 |
| HD 40307 c | 9.62 days | 0.0799 AU | — | 1868.5 M⊕ | Radial Velocity, 2009 |
| HD 40307 d | 20.4 days | 0.132 AU | — | 1775.4 M⊕ | Radial Velocity, 2009 |
| HD 40307 f | 51.8 days | 0.247 AU | 2.13 R⊕ estimated | 5.2 M⊕ minimum | Radial Velocity, 2013 |
| HD 40307 g disputed | 197.8 days | 0.600 AU | 2.56 R⊕ estimated | 7.1 M⊕ minimum | Radial Velocity, 2013 |
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 4,956 K, 0.23 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 0.48 to 0.86 AU. 1 of its 5 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 42 years ago, within living memory.