Star · M3III
47 Eri
47 Eri is a giant star of spectral type M3III in the constellation Eridanus, 772.9 light-years from the Sun.
| Other names | HIP 21296 |
|---|---|
| Constellation | Eridanus |
| Distance | 772.9 light-years (237.0 pc) |
| Apparent magnitude | magnitude 5.20 |
| Absolute magnitude | magnitude −1.67 |
| Spectral type | M3III |
| Surface temperature | 3,510 K |
| Luminosity | 2,270 L☉ |
| Radius | 129 R☉ |
| Mass | 8.27 M☉ (estimated) |
| Right ascension (J2000) | 4h 34m 11.6s |
| Declination (J2000) | −8° 13′ 53″ |
| Space velocity (relative to the Sun) | 28.7 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.20). Visible from the whole Southern Hemisphere and north to latitude 82° N. 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 1253. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 14 million years.
The Sun seen from there
From a planet around 47 Eri, the Sun would look like a star of magnitude 11.70, in the direction where our sky has the constellation Hercules. 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.