| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Canes Venatici |
| Right ascension | 13h 34m 47.80827s[2] |
| Declination | +37° 10′ 56.6979″[2] |
| Apparent magnitude (V) | 4.91[3] |
| Characteristics | |
| Spectral type | kA6hF1mF2[4](F2 IV + K0 IV)[5] |
| B−Vcolor index | 0.404±0.010[3] |
| Variable type | RS CVn[5] |
| Astrometry | |
| Radial velocity (Rv) | 6.43±0.24[3] km/s |
| Proper motion (μ) | RA: +84.63[2]mas/yr Dec.: −9.34[2]mas/yr |
| Parallax (π) | 21.90±0.23 mas[2] |
| Distance | 149 ± 2 ly (45.7 ± 0.5 pc) |
| Absolute magnitude (MV) | 1.61[3] |
| Orbit[6] | |
| Period (P) | 2.613214 d |
| Semi-major axis (a) | 0.017 AU |
| Eccentricity (e) | 0.00 |
| Inclination (i) | 171.1° |
| Longitude of the node (Ω) | 89±10° |
| Periastronepoch (T) | 2,445,766.655 |
| Details | |
| BH CVn A | |
| Mass | 1.5[6] M☉ |
| Radius | 2.6[6] R☉ |
| Luminosity | 19.01[3] L☉ |
| Surface gravity (log g) | 3.61±0.14[7] cgs |
| Temperature | 6,569±223[7] K |
| Metallicity[Fe/H] | −0.20[3] dex |
| Age | 1.36[7] Gyr |
| BH CVn B | |
| Mass | 0.8[6] M☉ |
| Radius | 3.4[6] R☉ |
| Other designations | |
| BH CVn,BD+37°2426,FK5 502,HD 118216,HIP 66257,HR 5110,SAO 63623[8] | |
| Database references | |
| SIMBAD | data |
HR 5110, also known asBH Canum Venaticorum, is abinary star[6] system in thenorthernconstellation ofCanes Venatici. It is visible to thenaked eye with anapparent visual magnitude of 4.91.[3] Based upon an annualparallax shift of21.90±0.23 mas,[2] it is located 149 light-years away. The system is moving further from theSun with a heliocentricradial velocity of 6.4 km/s.[3]
This is a close binary system with an orbital period of 2.6 days and an orbital plane that is oriented nearly face-on.[6] It may be considered anAlgol-typesemidetached binary. The hotter primary component has astellar classification of F2 IV,[5] indicating it is anevolvingsubgiant star that is leaving themain sequence after consuming the hydrogen at its core.
Douglas S. Hallet al. discovered that HR 5110 is avariable star, in 1978.[9] It was given itsvariable star designation, BH Canum Venaticorum, in 1981.[10] HR 5110 is classified as aRS Canum Venaticorum variable system, primarily due tochromospheric activity in the secondary component.[5] This star has a classification of K0 IV, matching aK-typesubgiant star.[5] Based upon the close separation of the pair and the class of the secondary component, that latter is probably filling itsroche lobe. This star is most likely the source of the radio emission from this system, and the alignment of this signal is consistent with a polarstarspot.[6]
