Star · F5I
HIP 21517
HIP 21517 is a supergiant star of spectral type F5I in the constellation Taurus, 2,072 light-years from the Sun.
| Constellation | Taurus |
|---|---|
| Distance | 2,072 light-years (635.3 pc) |
| Apparent magnitude | magnitude 6.49 |
| Absolute magnitude | magnitude −2.52 |
| Spectral type | F5I |
| Surface temperature | 5,250 K |
| Luminosity | 1,090 L☉ |
| Radius | 39.9 R☉ |
| Mass | 6.7 M☉ (estimated) |
| Right ascension (J2000) | 4h 37m 14.8s |
| Declination (J2000) | +18° 32′ 35″ |
| Space velocity (relative to the Sun) | 20.7 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 6.49). Visible from the whole Northern Hemisphere and south to latitude 71° S. North of latitude 71° N it never sets. It stands highest at midnight in November, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 47 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 37 million years.
The Sun seen from there
From a planet around HIP 21517, the Sun would look like a star of magnitude 13.84, in the direction where our sky has the constellation Ophiuchus. It would be invisible to the naked eye.
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.