Star · K1III
α Hor
α Hor is a giant star of spectral type K1III in the constellation Horologium, 117.7 light-years from the Sun.
| Other names | HIP 19747 |
|---|---|
| Constellation | Horologium |
| Distance | 117.7 light-years (36.1 pc) |
| Apparent magnitude | magnitude 3.85 |
| Absolute magnitude | magnitude 1.06 |
| Spectral type | K1III |
| Surface temperature | 4,550 K |
| Luminosity | 56.8 L☉ |
| Radius | 12.1 R☉ |
| Mass | 2.88 M☉ (estimated) |
| Right ascension (J2000) | 4h 14m 00.1s |
| Declination (J2000) | −42° 17′ 40″ |
| Space velocity (relative to the Sun) | 41.7 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 3.85). Visible from the whole Southern Hemisphere and north to latitude 48° N. South of latitude 48° S 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 1908. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 2.1 million years.
The Sun seen from there
From a planet around α Hor, the Sun would look like a star of magnitude 7.62, in the direction where our sky has the constellation Hercules. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- HIP 20630 6.99 light-years
- HIP 20048 9.70 light-years
- HIP 21934 12.4 light-years
- HIP 22281 13.5 light-years
- HIP 18538 13.9 light-years
- HIP 19976 14.0 light-years
- WISEA J034227.44-462252.0 14.3 light-years
- HIP 20781 15.0 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.