Star · K
HAT-P-17
HAT-P-17 is a main-sequence star of spectral type K in the constellation Cygnus, 301.5 light-years from the Sun. It is orbited by 2 confirmed exoplanet(s).
| Constellation | Cygnus |
|---|---|
| Distance | 301.5 light-years (92.4 pc) |
| Apparent magnitude | magnitude 10.48 |
| Absolute magnitude | magnitude 5.65 |
| Spectral type | K |
| Surface temperature | 5,250 K |
| Luminosity | 0.514 L☉ |
| Radius | 0.87 R☉ |
| Mass | 0.99 M☉ |
| Age | 7.0 billion years |
| Metallicity [Fe/H] | 0.00 |
| Right ascension (J2000) | 21h 38m 08.7s |
| Declination (J2000) | +30° 29′ 19″ |
| Space velocity (relative to the Sun) | 69.0 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 10.48. Visible from the whole Northern Hemisphere and south to latitude 60° S. North of latitude 60° N it never sets. It stands highest at midnight in August, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1725. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 5.3 million years.
The Sun seen from there
From a planet around HAT-P-17, the Sun would look like a star of magnitude 9.66, in the direction where our sky has the constellation Antlia. It would be invisible to the naked eye.
Planets
- HAT-P-17 b 10.3-day orbit · 11.8 R⊕
- HAT-P-17 c 5,580-day orbit · 13.1 R⊕
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- HIP 107288 18.0 light-years
- HIP 106081 18.8 light-years
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.