75 Cygni

75 Cygni is a binary star[6] system in the northern constellation of Cygnus. It is visible to the naked eye as a dim, reddish-hued point of light with an apparent visual magnitude of 5.09.[2] The system is located at a distance of about 434 light years from the Sun, based on parallax, and is drifting closer with a radial velocity of −29 km/s.[1]

75 Cygni
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus
Right ascension  21h 40m 11.10795s[1]
Declination +43° 16′ 25.8161″[1]
Apparent magnitude (V) 5.09[2]
Characteristics
Evolutionary stage red giant
Spectral type M1IIIab[3]
B−V color index 1.601±0.006[2]
Variable type suspected[4]
Astrometry
Radial velocity (Rv)−29.25±0.14[1] km/s
Proper motion (μ) RA: +62.366[1] mas/yr
Dec.: +15.488[1] mas/yr
Parallax (π)7.5210 ± 0.1706[1] mas
Distance434 ± 10 ly
(133 ± 3 pc)
Absolute magnitude (MV)−0.36[2]
Details
Radius44.61+3.12
−7.77[1] R☉
Luminosity438.5±11.5[1] L☉
Temperature3,954+397
−131[1] K
Other designations
75 Cyg, NSV 13834, BD+42°4177, GC 30338, HD 206330, HIP 106999, HR 8284, SAO 51167, WDS J21402+4316[5]
Database references
SIMBADdata

The pair had an angular separation of 2.7″ as of 2008, with the companion having a visual magnitude of 10.7.[6] The brighter magnitude 5.18[6] primary is an aging red giant star with a stellar classification of M1IIIab.[3] Having exhausted the supply of hydrogen at its core, it has expanded to around 45[1] times the radius of the Sun. It is a suspected variable star of unknown type and amplitude.[4] The star is radiating 439[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,954 K.[1]

An optical companion, with a spectral type of K, is a few arcseconds away and has an apparent magnitude of 10.14.[7]

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.
  3. Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
  4. Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, GCVS 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S.
  5. "75 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-07-22.
  6. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x.
  7. "BD+42 4177C". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-07-22.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.