Star · B9IV
HIP 21251
HIP 21251 is a subgiant star of spectral type B9IV in the constellation Taurus, 475.1 light-years from the Sun.
| Constellation | Taurus |
|---|---|
| Distance | 475.1 light-years (145.7 pc) |
| Apparent magnitude | magnitude 6.24 |
| Absolute magnitude | magnitude 0.42 |
| Spectral type | B9IV |
| Surface temperature | 9,260 K |
| Luminosity | 71.3 L☉ |
| Radius | 3.28 R☉ |
| Mass | 3.07 M☉ (estimated) |
| Right ascension (J2000) | 4h 33m 32.8s |
| Declination (J2000) | +18° 01′ 01″ |
| Space velocity (relative to the Sun) | 27.0 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 6.24). Visible from the whole Northern Hemisphere and south to latitude 72° S. North of latitude 72° 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 the year 1551. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 8.4 million years.
The Sun seen from there
From a planet around HIP 21251, the Sun would look like a star of magnitude 10.65, 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.