Star · K3
HAT-P-20
HAT-P-20 is a main-sequence star of spectral type K3 in the constellation Gemini, 232.9 light-years from the Sun. It is orbited by 1 confirmed exoplanet(s).
| Constellation | Gemini |
|---|---|
| Distance | 232.9 light-years (71.4 pc) |
| Apparent magnitude | magnitude 11.39 |
| Absolute magnitude | magnitude 7.12 |
| Spectral type | K3 |
| Surface temperature | 4,600 K |
| Luminosity | 0.19 L☉ |
| Radius | 0.694 R☉ |
| Mass | 0.756 M☉ |
| Age | 6.7 billion years |
| Metallicity [Fe/H] | 0.35 |
| Right ascension (J2000) | 7h 27m 39.9s |
| Declination (J2000) | +24° 20′ 10″ |
| Space velocity (relative to the Sun) | 37.8 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 11.39. Visible from the whole Northern Hemisphere and south to latitude 66° S. North of latitude 66° N it never sets. It stands highest at midnight in January, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1793. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 4.1 million years.
The Sun seen from there
From a planet around HAT-P-20, the Sun would look like a star of magnitude 9.10, in the direction where our sky has the constellation Sagittarius. It would be invisible to the naked eye.
Planets
- HAT-P-20 b 2.88-day orbit · 9.72 R⊕
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- HIP 36898 8.82 light-years
- HIP 35459 16.2 light-years
- HIP 37579 17.3 light-years
- HIP 34640 17.5 light-years
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.