Star · B9
84 UMa
84 UMa is a main-sequence star of spectral type B9 in the constellation Ursa Major, 303.6 light-years from the Sun.
| Other names | HIP 67231 |
|---|---|
| Constellation | Ursa Major |
| Distance | 303.6 light-years (93.1 pc) |
| Apparent magnitude | magnitude 5.68 |
| Absolute magnitude | magnitude 0.84 |
| Spectral type | B9 |
| Surface temperature | 10,640 K |
| Luminosity | 60.4 L☉ |
| Radius | 2.29 R☉ |
| Mass | 2.93 M☉ (estimated) |
| Right ascension (J2000) | 13h 46m 35.7s |
| Declination (J2000) | +54° 25′ 58″ |
| Space velocity (relative to the Sun) | 8.7 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 5.68). Visible from the whole Northern Hemisphere and south to latitude 36° S. North of latitude 36° N it never sets. It stands highest at midnight in April, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1722. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 5.4 million years.
The Sun seen from there
From a planet around 84 UMa, the Sun would look like a star of magnitude 9.67, 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):
- 81 UMa 10.9 light-years
- Liesma 10.9 light-years
- HIP 66846 11.9 light-years
- HIP 67005 12.8 light-years
- HIP 66501 13.1 light-years
- SDSS J132926.03+531733.9 15.0 light-years
- HIP 66700 16.9 light-years
- HIP 65645 16.9 light-years
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.