BP Circini
Star in the constellation Circinus
From Wikipedia, the free encyclopedia
BP Circini is a binary star system in the southern constellation of Circinus. It is located at a distance of approximately 3,300 light years from the Sun based on parallax.[2]
Right ascension14h 46m 41.98011s[2]
Declination−61° 27′ 42.9903″[2]
Apparentmagnitude(V)7.37 - 7.71[3]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Circinus |
| Right ascension | 14h 46m 41.98011s[2] |
| Declination | −61° 27′ 42.9903″[2] |
| Apparent magnitude (V) | 7.37 - 7.71[3] |
| Characteristics | |
| Spectral type | F2/3II + B6V[4] |
| B−V color index | 0.649±0.020[5] |
| Astrometry | |
| Proper motion (μ) | RA: −5.355[2] mas/yr Dec.: −3.920[2] mas/yr |
| Parallax (π) | 0.9952±0.0402 mas[2] |
| Distance | 3,300 ± 100 ly (1,000 ± 40 pc) |
| Absolute magnitude (MV) | −2.91[6] |
| Orbit[6] | |
| Period (P) | 20 yr |
| Semi-major axis (a) | 15.8 AU |
| Details | |
| A | |
| Mass | 5[7] M☉ |
| Radius | 30.38+6.93 −6.50[2] R☉ |
| Luminosity | 917±54[2] L☉ |
| Surface gravity (log g) | 2.75[8] cgs |
| Temperature | 6356±23[8] K |
| B | |
| Mass | 4.7[6] M☉ |
| Surface gravity (log g) | 4.0±0.5[7] cgs |
| Temperature | 16,000±1,000[7] K |
| Other designations | |
| BP Cir, CD−60°5320, HD 129708, HIP 72264, SAO 252879, WDS J14467-6128A[9] | |
| Database references | |
| SIMBAD | data |
The variability of this star was discovered by D. W. Kurtz in 1979.[7] A small-amplitude Cepheid variable,[8] its apparent magnitude ranges from 7.37 to 7.71 over 2.39810 days.[3] A spectroscopic binary, the primary is a yellow-white bright giant of spectral type F2 or F3II.[4] The spectrum shows peculiarities in the metallic lines.[10] The secondary is a 4.7 solar mass (M☉) blue-white main sequence star of spectral type B6.[6]