Rho Ursae Majoris
Rho Ursae Majoris (ρ UMa) is the Bayer designation for a solitary star in the northern circumpolar constellation of Ursa Major. It is faintly visible to the naked eye with an apparent visual magnitude of 4.74. The distance to this star, based upon an annual parallax shift of 10.37 mas, is around 315 light years.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 09h 02m 32.69092s |
| Declination | +67° 37′ 46.6280″ |
| Apparent magnitude (V) | 4.74 |
| Characteristics | |
| Spectral type | M3 III |
| U−B color index | +1.84 |
| B−V color index | +1.56 |
| Astrometry | |
| Radial velocity (Rv) | 4.75±0.19 km/s |
| Proper motion (μ) | RA: −22.83 mas/yr Dec.: +18.13 mas/yr |
| Parallax (π) | 10.37 ± 0.25 mas |
| Distance | 315 ± 8 ly (96 ± 2 pc) |
| Absolute magnitude (MV) | +0.06 |
| Details | |
| Radius | 58 R☉ |
| Luminosity | 464 L☉ |
| Temperature | 3,725 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
With a stellar classification of M3 III, this is a red giant star on the asymptotic giant branch. It is a suspected small amplitude variable. The measured angular diameter of the star after correcting for limb darkening is 5.64±0.15 mas, which, at the estimated distance of this star, yields a physical size of about 58 times the radius of the Sun. It is radiating 464 times the solar luminosity from its outer atmosphere at an effective temperature of about 3,725 K. Based upon its motion through space, there is a 60.6% chance that this star is a member of the Sirius stream.