| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 11h 03m 43.67152s |
| Declination | +61° 45′ 03.7249″ |
| Apparent magnitude (V) | 1.79 |
| Characteristics | |
| Spectral type | K0III + F0V |
| U−B color index | +0.93 |
| B−V color index | +1.07 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | −9.4±0.3 km/s |
| Proper motion (μ) | RA: –134.11 mas/yr Dec.: –34.70 mas/yr |
| Parallax (π) | 26.54 ± 0.48 mas |
| Distance | 123 ± 2 ly (37.7 ± 0.7 pc) |
| Absolute magnitude (MV) | −1.10±0.04 |
| Details | |
| α UMa A | |
| Mass | 3.44±0.11 M☉ |
| Radius | 17.03±0.13 R☉ |
| Luminosity | 165.1±8.3 L☉ |
| Surface gravity (log g) | 2.20 cgs |
| Temperature | 5,012±65 K |
| Metallicity [Fe/H] | −0.20±0.07 dex |
| Rotational velocity (v sin i) | 2.6±1.0 km/s |
| Age | 280±30 Myr |
| α UMa B | |
| Mass | ~1.6 M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Dubhe or Alpha Ursae Majoris is a red giant star in the constellation of Ursa Major. It is 27 times wider than the Sun.