Star · M1III
τ¹ Ser
τ¹ Ser is a giant star of spectral type M1III in the constellation Serpens, 827.6 light-years from the Sun.
| Other names | HIP 75530 |
|---|---|
| Constellation | Serpens |
| Distance | 827.6 light-years (253.7 pc) |
| Apparent magnitude | magnitude 5.16 |
| Absolute magnitude | magnitude −1.86 |
| Spectral type | M1III |
| Surface temperature | 3,580 K |
| Luminosity | 2,390 L☉ |
| Radius | 127 R☉ |
| Mass | 8.38 M☉ (estimated) |
| Right ascension (J2000) | 15h 25m 47.4s |
| Declination (J2000) | +15° 25′ 41″ |
| Space velocity (relative to the Sun) | 24.6 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.16). Visible from the whole Northern Hemisphere and south to latitude 75° S. North of latitude 75° N it never sets. It stands highest at midnight in May, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1198. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 15 million years.
The Sun seen from there
From a planet around τ¹ Ser, the Sun would look like a star of magnitude 11.85, in the direction where our sky has the constellation Eridanus. 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.