BC Canis Minoris

BC Canis Minoris is a variable star in the equatorial constellation of Canis Minor. It has a reddish hue and is just barely visible to the naked eye with an apparent visual magnitude that fluctuates around 6.30.[2] The distance to this object is approximately 520 light years based on parallax,[1] but it is drifting closer with a radial velocity of −67 km/s.[2]

BC Canis Minoris

Observation data Epoch J2000      Equinox J2000
Constellation	Canis Minor
Right ascension	07^h 52^m 07.19000^s[1]
Declination	03° 16′ 38.4465″[1]
Apparent magnitude (V)	6.30[2] (6.14 to 6.42)[3]
Characteristics
Evolutionary stage	AGB[4]
Spectral type	M4/5III[5]
B−V color index	1.464±0.015[2]
Variable type	SRb[3]
Astrometry
Radial velocity (Rv)	−66.91±0.24[2] km/s
Proper motion (μ)	RA: +49.415[1] mas/yr Dec.: −78.835[1] mas/yr
Parallax (π)	6.2916 ± 0.1748[1] mas
Distance	520 ± 10 ly (159 ± 4 pc)
Absolute magnitude (MV)	0.36[2]
Details
Radius	60.4+7.6 −10.3[1] R☉
Luminosity	496.7±15.9[1] L☉
Temperature	3,507+344 −201[1] K
Other designations
BC CMi, BD+03°1824, HD 64052, HIP 38406, HR 3061, SAO 116054[6]
Database references
SIMBAD	data

This is an aging red giant star currently on the asymptotic giant branch[4] with a stellar classification of M4/5III.[5] It is a semi-regular variable of subtype SRb[3] with measured pulsation periods of 27.7, 143.3 and 208.3 days, and an average visual magnitude of 6.30.[7] With the supply of hydrogen at its core exhausted, it has cooled and expanded off the main sequence and now has around 60[1] times the girth of the Sun. On average, the star is radiating about 497[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 3,507 K.[1]

References

1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
3. Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
4. Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". Astronomical Journal. 104 (1): 275–313. Bibcode:1992AJ....104..275E. doi:10.1086/116239.
5. Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
6. "BC CMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-12-13.
7. Tabur, V.; Bedding, T. R. (2009). "Long-term photometry and periods for 261 nearby pulsating M giants". Monthly Notices of the Royal Astronomical Society. 400 (4): 1945–61. arXiv:0908.3228. Bibcode:2009MNRAS.400.1945T. doi:10.1111/j.1365-2966.2009.15588.x. S2CID 15358380.