Star · K0 V
K2-139
K2-139 is a main-sequence star of spectral type K0 V in the constellation Sagittarius, 498.9 light-years from the Sun. It is orbited by 1 confirmed exoplanet(s).
| Constellation | Sagittarius |
|---|---|
| Distance | 498.9 light-years (153.0 pc) |
| Apparent magnitude | magnitude 11.74 |
| Absolute magnitude | magnitude 5.82 |
| Spectral type | K0 V |
| Surface temperature | 5,370 K |
| Luminosity | 0.502 L☉ |
| Radius | 0.88 R☉ |
| Mass | 0.96 M☉ |
| Age | 1.8 billion years |
| Metallicity [Fe/H] | 0.24 |
| Right ascension (J2000) | 19h 16m 16.0s |
| Declination (J2000) | −17° 54′ 38″ |
| Space velocity (relative to the Sun) | 41.7 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.74. Visible from the whole Southern Hemisphere and north to latitude 72° N. South of latitude 72° S it never sets. It stands highest at midnight in July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1527. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 8.9 million years.
The Sun seen from there
From a planet around K2-139, the Sun would look like a star of magnitude 10.75, in the direction where our sky has the constellation Gemini. It would be invisible to the naked eye.
Planets
- K2-139 b 28.4-day orbit · 9.11 R⊕
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.