Star · G4III
τ Per
τ Per is a giant star of spectral type G4III in the constellation Perseus, 263.6 light-years from the Sun.
| Other names | HIP 13531 |
|---|---|
| Constellation | Perseus |
| Distance | 263.6 light-years (80.8 pc) |
| Apparent magnitude | magnitude 3.93 |
| Absolute magnitude | magnitude −0.61 |
| Spectral type | G4III |
| Surface temperature | 5,410 K |
| Luminosity | 177 L☉ |
| Radius | 15.2 R☉ |
| Mass | 3.99 M☉ (estimated) |
| Right ascension (J2000) | 2h 54m 15.5s |
| Declination (J2000) | +52° 45′ 45″ |
| Space velocity (relative to the Sun) | 10.4 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 3.93). Visible from the whole Northern Hemisphere and south to latitude 37° S. North of latitude 37° 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 1762. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 4.7 million years.
The Sun seen from there
From a planet around τ Per, the Sun would look like a star of magnitude 9.37, in the direction where our sky has the constellation Lupus. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- HIP 13584 9.84 light-years
- HIP 12984 16.2 light-years
- HIP 15675 19.6 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.