32 Cygni (32 Cyg, Omicron2 Cyg, ο2 Cyg, ο3 Cyg) is abinary star system in theCygnusconstellation. It is a 4th magnitude star, which can be seen with the naked eye undersuitably dark skies.Parallax measurements give an estimated distance of 1,000 light-years (307 parsecs) from the Earth.[1] However, Schröder et al. (2007) suggest the actual value, after correcting forMalmquist bias, may be closer to 1,174 light-years (360 parsecs).[6] Although it is a spectrsocopic binary with components that cannot be separated visually, it has two entries in theHenry Draper Catalogue, with identical magnitudes and positions, but showing the spectral types of the two components.[14]
TheBayer letter ο has been variously applied to two or three of the stars 30, 31, and 32 Cygni. 32 Cygni has been designated as either ο2 or ο3 Cygni. For clarity, it is preferred to use theFlamsteed designation 32 Cygni rather than one of the Bayer designations.[13]
32 Cygni B, the companion star, is three times asluminous as the Sun and four timesas massive.[6] It has a much higher effective temperature of 16,200 K[12] and is radiating over 300 times the Sun's luminosity.[6] This star has the blue-white hue of a B7 starmain sequence star.
The two stars form aneclipsing binary system (variable star designation: V1488 Cyg) similar toAlgol. Theorbital plane of the two stars is nearly aligned with the line of sight from the Earth, so that the supergiant star eclipses the secondary component once per orbit. During an eclipse,emission lines can be seen in thespectrum of this system. These originate in thestellar wind escaping from the supergiant star. In a volume around the B star, this wind becomesionized, resulting in a circumstellarH II region.[17] The supergiant star is losing mass at the rate of1.3×10−8 times themass of the Sun per year, or the equivalent of the Sun's mass every 77 million years.[6]
^abcJohnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars",Communications of the Lunar and Planetary Laboratory,4 (99): 99,Bibcode:1966CoLPL...4...99J.
^abSamus, 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.Bibcode:2009yCat....102025S.
^abKostjuk, N. D. (2004). "VizieR Online Data Catalog: HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index (Kostjuk, 2002)".VizieR On-line Data Catalog: IV/27A. Originally Published in: Institute of Astronomy of Russian Academy of Sciences (2002).4027.Bibcode:2004yCat.4027....0K.
^Nesterov, V. V.; Kuzmin, A. V.; Ashimbaeva, N. T.; Volchkov, A. A.; Röser, S.; Bastian, U. (1995). "The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars".Astronomy and Astrophysics.110: 367.Bibcode:1995A&AS..110..367N.
^Dommanget, J.; Nys, O. (1994). "Catalogue des composantes d'etoiles doubles et multiples (CCDM) premiere edition - Catalogue of the components of double and multiple stars (CCDM) first edition".Com. De l'Observ. Royal de Belgique.115: 1.Bibcode:1994CoORB.115....1D.
