Star · K2III
Unukalhai
Unukalhai is a giant star of spectral type K2III in the constellation Serpens, 74.2 light-years from the Sun.
| Other names | α Ser · Gl 596.2 · HIP 77070 |
|---|---|
| Constellation | Serpens |
| Distance | 74.2 light-years (22.8 pc) |
| Apparent magnitude | magnitude 2.63 |
| Absolute magnitude | magnitude 0.84 |
| Spectral type | K2III |
| Surface temperature | 4,370 K |
| Luminosity | 79 L☉ |
| Radius | 15.5 R☉ |
| Mass | 3.17 M☉ (estimated) |
| Right ascension (J2000) | 15h 44m 16.1s |
| Declination (J2000) | +6° 25′ 33″ |
| Space velocity (relative to the Sun) | 15.5 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 2.63). Visible from the whole Northern Hemisphere and south to latitude 84° S. 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 1952. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.3 million years.
The Sun seen from there
From a planet around Unukalhai, the Sun would look like a star of magnitude 6.62, in the direction where our sky has the constellation Eridanus. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- ε Ser 3.95 light-years
- GJ 3917 7.20 light-years
- Gl 600 8.15 light-years
- WISE J151721.13+052929.3 9.21 light-years
- SDSS J152103.24+013142.7 9.90 light-years
- WISEA J160516.79+002139.0 10.5 light-years
- GJ 1193 10.6 light-years
- SDSS J153453.33+121949.2 11.6 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.