Star · K5III
31 Ori
31 Ori is a giant star of spectral type K5III in the constellation Orion, 500.5 light-years from the Sun.
| Other names | HIP 25737 |
|---|---|
| Constellation | Orion |
| Distance | 500.5 light-years (153.4 pc) |
| Apparent magnitude | magnitude 4.71 |
| Absolute magnitude | magnitude −1.22 |
| Spectral type | K5III |
| Surface temperature | 3,660 K |
| Luminosity | 1,170 L☉ |
| Radius | 85 R☉ |
| Mass | 6.83 M☉ (estimated) |
| Right ascension (J2000) | 5h 29m 44.0s |
| Declination (J2000) | −1° 05′ 32″ |
| Space velocity (relative to the Sun) | 20.2 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 4.71). Visible from the whole Southern Hemisphere and north to latitude 89° N. It stands highest at midnight in December, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1526. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 8.9 million years.
The Sun seen from there
From a planet around 31 Ori, the Sun would look like a star of magnitude 10.76, in the direction where our sky has the constellation Ophiuchus. 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.