Star · A2
ε Ser
ε Ser is a main-sequence star of spectral type A2 in the constellation Serpens, 72.0 light-years from the Sun.
| Other names | GJ 3921 · HIP 77622 |
|---|---|
| Constellation | Serpens |
| Distance | 72.0 light-years (22.1 pc) |
| Apparent magnitude | magnitude 3.71 |
| Absolute magnitude | magnitude 1.99 |
| Spectral type | A2 |
| Surface temperature | 8,600 K |
| Luminosity | 15.4 L☉ |
| Radius | 1.77 R☉ |
| Mass | 1.98 M☉ (estimated) |
| Right ascension (J2000) | 15h 50m 49.0s |
| Declination (J2000) | +4° 28′ 40″ |
| Space velocity (relative to the Sun) | 17.8 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 3.71). Visible from the whole Northern Hemisphere and south to latitude 86° 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 1954. 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 ε Ser, the Sun would look like a star of magnitude 6.55, 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):
- GJ 3917 3.93 light-years
- Unukalhai 3.95 light-years
- WISEA J160516.79+002139.0 6.87 light-years
- Gl 600 8.48 light-years
- SIMP J1619275+031350 9.14 light-years
- WISE J151721.13+052929.3 10.5 light-years
- SDSS J152103.24+013142.7 10.7 light-years
- SDSS J153453.33+121949.2 12.3 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.