CX CMa (CX Canis Majoris) is a blue variable star in the Canis Major constellation.[6][7] Discovery of this variable is usually credited to German Astronomer Cuno Hoffmeister in 1931, although this remains uncertain.[8]

CX Canis Majoris

A visual band light curve for CX Canis Majoris, plotted from All Sky Automated Survey data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Canis Major
Right ascension 07h 22m 00.98686s[2]
Declination −25° 52′ 35.9276″[2]
Apparent magnitude (V) 9.89 (-10.14) - 10.42[3]
Characteristics
Evolutionary stage B5V[4]
Variable type Algol[3]
Astrometry
Proper motion (μ) RA: −2.656[2] mas/yr
Dec.: 2.777[2] mas/yr
Parallax (π)0.7147 ± 0.0586 mas[2]
Distance4,600 ± 400 ly
(1,400 ± 100 pc)
Details
A
Mass5.9[5] M
Temperature15,200[5] K
B
Mass3.4[5] M
Temperature10,600[5] K
Other designations
CD−25 4424, TYC 6541-1691-1[6]
Database references
SIMBADdata

It is an eclipsing binary of Algol (detached)[3] whose magnitude varies between 9.9 and 10.4 with a period of 0.95462500 day (22.911000 hour).[7] The variability was first discovered in 1931.[9] Doubts arose because of scatter in the data and the small amplitude,[10] but the discovery was confirmed by 1949.[11] Its Algol-type light curve exhibits the O'Connell effect, meaning that there is a magnitude difference between subsequent maxima.[12]

The temperature of the secondary star has been estimated at 10,600 K and its mass at 3.4 M. The spectral type of the secondary star is estimated to be in the B8 to A0 range.[13]

References

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  1. ^ "ASAS All Star Catalogue". The All Sky Automated Survey. Retrieved 8 December 2021.
  2. ^ a b c d e 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.
  3. ^ a b c Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
  4. ^ Williams, S. J.; Gies, D. R.; Helsel, J. W.; Matson, R. A.; Caballero-Nieves, S. (2011). "ASAS Light Curves of Intermediate-mass Eclipsing Binary Stars and the Parameters of HI Mon". The Astronomical Journal. 142 (1): 5. arXiv:1104.3166. Bibcode:2011AJ....142....5W. doi:10.1088/0004-6256/142/1/5. S2CID 119229809.
  5. ^ a b c d Nelson, Robert H.; Terrell, Dirk (2004). "CX CMa - an Early-Type Detached Eclipsing Binary". Information Bulletin on Variable Stars. 5545: 1. Bibcode:2004IBVS.5545....1N.
  6. ^ a b "CX CMa". SIMBAD Astronomical Database. Strasbourg Astronomical Data Center. Retrieved 2016-09-01.
  7. ^ a b "VSX: Detail for CX CMa". The International Variable Star Index. American Association of Variable Star Observers. Retrieved 2016-09-01.
  8. ^ Milone, E. F. (1984). "Photometry &Spectroscopy of Southern O'Connell Effect Systems VY Cru, CX CMa, TU Cru, AQ Mon, &DQ Vel". Bulletin of the American Astronomical Society. 16: 506. Bibcode:1984BAAS...16..506M.
  9. ^ Hoffmeister, C. (1931). "316 neue Veränderliche". Astronomische Nachrichten. 242 (7): 131. Bibcode:1931AN....242..129H. doi:10.1002/asna.19312420702.
  10. ^ Florya, N. (1937). "Untersuchungen von 77 veränderlichen Sternen in Monoceros, Canis major und Puppis". Trudy Gosudarstvennogo Astronomicheskogo Instituta Im. P.K. Sternberga; T. 8. 8 (2): 5. Bibcode:1937TrSht...8....5F.
  11. ^ Deurinck, R. (1949). "Fourteen New Variable Stars in Canis Major, Puppis and Monoceros". Publications du Laboratoire d'Astronomie et de Géodésie de l'Université de Louvain. 12 (1ll): E17. Bibcode:1949PLAGL..12E..17D.
  12. ^ E. F. Milone (1984). "Photometry and Spectroscopy of Southern O'Connell Effect Systems VY Cru, CX CMa, TU Cru, AQ Mon, and DQ Vel". Bulletin of the American Astronomical Society. 16: 506. Bibcode:1984BAAS...16..506M.
  13. ^ Robert H. Nelson, Dirk Terrell (30 July 2004). "CX CMa - an early type detached eclipsing binary". Information Bulletin on Variable Stars. 5545 (5545): 1. Bibcode:2004IBVS.5545....1N.