R Canum Venaticorum
Star in the constellation Canes Venatici
From Wikipedia, the free encyclopedia
R Canum Venaticorum is a Mira variable star in the constellation Canes Venatici. It ranges between magnitudes 6.5 and 12.9 over a period of approximately 329 days.[3] It is too faint to be seen with the naked eye, but when it is near its maximum brightness it can be seen with binoculars.
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Canes Venatici |
| Right ascension | 13h 48m 57.0416s[2] |
| Declination | +39° 32′ 33.174″[2] |
| Apparent magnitude (V) | 6.5 - 12.9[3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | M5.5e-M9e[3] |
| U−B color index | +0.41[5] |
| B−V color index | +1.22[5] |
| Variable type | Mira[3] |
| Astrometry | |
| Radial velocity (Rv) | −6.80[6] km/s |
| Proper motion (μ) | RA: −1.115[2] mas/yr Dec.: −5.148[2] mas/yr |
| Parallax (π) | 2.1711±0.1262 mas[2] |
| Distance | 1,500 ± 90 ly (460 ± 30 pc) |
| Details | |
| Mass | 2.26[7] M☉ |
| Radius | 664[7] R☉ |
| Luminosity | 29,251[8] L☉ |
| Surface gravity (log g) | 2.19[9] cgs |
| Temperature | 3,108[8] K |
| Metallicity [Fe/H] | −0.25[9] dex |
| Other designations | |
| R CVn, SAO 63763, GSC 03027-00252, BD+40°2694, HD 120499, DO 14814, GC 18671, HIP 67410, HR 5199 | |
| Database references | |
| SIMBAD | data |
Thomas E. Espin discovered this variable star in 1888.[10] It appeared with its variable star designation, R Canum Venaticorum in Annie Jump Cannon's 1907 work Second Catalogue of Variable Stars.[11]
Having exhausted its core helium, R Canum Venaticorum is on the asymptotic giant branch, producing energy from concentric hydrogen and helium shells.[4]