Gamma Ursae Minoris
Gamma Ursae Minoris (γ Ursae Minoris, abbreviated Gamma UMi, γ UMi), also named Pherkad /ˈfɜːrkæd/, is a star in the northern constellation of Ursa Minor. Together with Beta Ursae Minoris (Kochab), it forms the end of the dipper pan of the "Little Dipper", which is an asterism forming the tail of the bear. Based upon parallax measurements obtained during the Hipparcos mission, it is approximately 487 light-years (149 parsecs) from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 15h 20m 43.71604s |
| Declination | +71° 50′ 02.4596″ |
| Apparent magnitude (V) | +3.05 |
| Characteristics | |
| Spectral type | A2 III |
| U−B color index | +0.08 |
| B−V color index | +0.09 |
| Astrometry | |
| Radial velocity (Rv) | −3.9 km/s |
| Proper motion (μ) | RA: −17.73 mas/yr Dec.: +17.90 mas/yr |
| Parallax (π) | 6.70 ± 0.11 mas |
| Distance | 487 ± 8 ly (149 ± 2 pc) |
| Absolute magnitude (MV) | –2.84 |
| Details | |
| Radius | 15 R☉ |
| Luminosity | 1,100 L☉ |
| Surface gravity (log g) | 2.53 cgs |
| Temperature | 8,280 K |
| Rotational velocity (v sin i) | 180 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
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