K2-139 is 502 light-years from the Sun. The NASA Exoplanet Archive lists 1 planet around this K0 V star; the first was found in 2017 by transit (K2).
Fly there in 3DK2-139 b goes round its star every 28.4 days, 3 times as often as Mercury goes round the Sun.
| Spectral type | K0 V |
| Surface temperature | 5,370 K |
| Mass | 0.96 solar masses |
| Radius | 0.88 solar radii |
| Luminosity | 0.5018 times the Sun |
| Apparent magnitude | 11.652 |
| Age | about 1.8 billion years |
| Distance from the Sun | 501.8 light-years (153.9 parsecs) |
| Position (J2000) | RA 289.0667°, Dec -17.9107° |
| Constellation | Sagittarius |
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| K2-139 b | 28.4 days | 0.180 AU | 9.11 R⊕ | 123 M⊕ | Transit, 2017 |
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 5,370 K, 0.50 times as bright as the Sun, the habitable zone, where starlight could keep water liquid on a rocky surface, runs from about 0.69 to 1.23 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 502 years ago, around 1520.