47 Boötis
| Observation data Epoch J2000 Equinox J2000  | |
|---|---|
| Constellation | Boötes | 
| Right ascension | 15h 05m 25.83464s | 
| Declination | +48° 09′ 03.4943″ | 
| Apparent magnitude (V) | 5.581 | 
| Characteristics | |
| Evolutionary stage | main sequence | 
| Spectral type | A0 Vs | 
| B−V color index | −0.005±0.003 | 
| Variable type | suspected | 
| Astrometry | |
| Radial velocity (Rv) | −12.63±0.73 km/s | 
| Proper motion (μ) |  RA: −65.912 mas/yr  Dec.: +28.641 mas/yr  | 
| Parallax (π) | 12.4980±0.0766 mas | 
| Distance | 261 ± 2 ly  (80.0 ± 0.5 pc)  | 
| Absolute magnitude (MV) | 0.97 | 
| Details | |
| 47 Boo A | |
| Mass | 2.46±0.02 M☉ | 
| Radius | 1.8 R☉ | 
| Luminosity | 45.7+2.2 −2.0 L☉  | 
| Surface gravity (log g) | 4.32 cgs | 
| Temperature | 10,130 K | 
| Rotational velocity (v sin i) | 54.8±1.6 km/s | 
| Other designations | |
| k Boo, 47 Boo, NSV 6934, BD+48°2262, FK5 1395, GC 20308, HD 133962, HIP 73841, HR 5627, SAO 45370, ADS 9500, CCDM 15054+4809 | |
| Database references | |
| SIMBAD | data | 
47 Boötis is a binary star system in the northern constellation of Boötes, located 261 light years away from the Sun. It has the Bayer designation k Boötis; 47 Boötis is the Flamsteed designation. The system is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.58. It is moving closer to the Earth with a heliocentric radial velocity of −13 km/s.
The primary member of the system, designated component A, is an A-type main-sequence star with a stellar classification of A0 Vs. The 's' indicates sharp lines as it has a moderate rotation rate with a projected rotational velocity of 55 km/s. It is a suspected variable star of unknown type. The star has 2.46 times the mass of the Sun and is radiating 46 times the Sun's luminosity from its photosphere at an effective temperature of 10,130 K.
The companion, component B, is a magnitude 13.3 star located at an angular separation of 6.2 arcseconds away from the primary.