BU Canis Minoris is a quadruple star system in the equatorial constellation of Canis Minor. It has the Henry Draper Catalogue designation of HD 65241, while BU Canis Minoris is its variable star designation. The system is a challenge to view with the naked eye, having a peak apparent visual magnitude of 6.42.[3] It is located at a distance of approximately 700 light years from the Sun based on parallax,[2] and is drifting further away with a radial velocity of about +34 km/s.[3]

BU Canis Minoris

A light curve for BU Canis Minoris, plotted from TESS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Canis Minor
Right ascension 07h 58m 05.89734s[2]
Declination 07° 12′ 48.7030″[2]
Apparent magnitude (V) 6.42[3]
Characteristics
Spectral type A0V[4]
B−V color index −0.031±0.008[3]
Astrometry
Radial velocity (Rv)+34.0±6.5[3] km/s
Proper motion (μ) RA: −9.407[2] mas/yr
Dec.: −11.835[2] mas/yr
Parallax (π)4.0663 ± 0.0568 mas[2]
Distance800 ± 10 ly
(246 ± 3 pc)
Absolute magnitude (MV)−0.38[3]
Details[5]
BU CMi Aa
Mass3.40 ± 0.10 M
Radius2.51 ± 0.05 R
Surface gravity (log g)4.088 ± 0.010 cgs
Temperature10130 ± 80 K
BU CMi Ab
Mass3.11 ± 0.10 M
Radius1.80 ± 0.05 R
Surface gravity (log g)4.338 ± 0.010 cgs
Temperature9740 ± 80 K
BU CMi Ba
Mass3.29 ± 0.10 M
Radius2.31 ± 0.05 R
Surface gravity (log g)4.148 ± 0.010 cgs
Temperature10180 ± 80 K
BU CMi Bb
Mass3.29 ± 0.10 M
Radius2.04 ± 0.05 R
Surface gravity (log g)4.259 ± 0.010 cgs
Temperature9890 ± 80 K
Other designations
BU CMi, BD+07°1879, HD 65241, HIP 38945, HR 3103, SAO 116179[6]
Database references
SIMBADdata

In 2021, BU Canis Majoris was found to be composed to two eclipsing binaries, totalling four stars. Both pairs are double-lined spectroscopic binary systems that form Algol-like eclipsing binaries.[5] The orbits of both systems are somewhat eccentric.[5] The brightness of the system decreases from 6.44 down to 6.53 during the primary eclipse.[7] It has a stellar classification of A0V,[4] which matches an A-type main-sequence star that is generating energy through hydrogen fusion at its core. In reality, however, all four stars are nearly equal in properties, and have masses from 3.1 to 3.4 solar masses.[5] The system is about 200 million years old.[5]

References edit

  1. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. ^ a b c d e f 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.
  3. ^ a b c d e f 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.
  4. ^ a b Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819
  5. ^ a b c d e Volkov, I. M.; Kravtsova, A. S.; Chochol, D. (2021). "BU CMi as a Quadruple Doubly Eclipsing System". Astronomy Reports. 65 (9): 826–838. arXiv:2107.09116. Bibcode:2021ARep...65..826V. doi:10.1134/S1063772921090080. S2CID 236133942.
  6. ^ "BU CMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-12-11.
  7. ^ 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.