B Persei


b Persei
Perseus constellation map.svg
Red circle.svg
Location of b Persei (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Perseus
Right ascension 04h 18m 14.61690s[1]
Declination +50° 17′ 43.8058″[1]
Apparent magnitude (V) 4.52 - 4.68[2]
Spectral type A1III[3]
B−V color index +0.04[4]
Variable type Ellipsoidal[2]
Radial velocity (Rv)19.8 ± 0.9[5] km/s
Proper motion (μ) RA: 45.42 ± 0.40[1] mas/yr
Dec.: -56.72 ± 0.32[1] mas/yr
Parallax (π)10.40 ± 0.35[1] mas
Distance310 ± 10 ly
(96 ± 3 pc)
Absolute magnitude (MV)0.3[6]
Primaryb Persei A
Companionb Persei C
Period (P)701.76 days
Semi-major axis (a)5.09 mas
Eccentricity (e)0.235
Inclination (i)83.46°
Longitude of the node (Ω)115.29°
Periastron epoch (T)2440143.3984
Argument of periastron (ω)
Mass2.25[6] M
Radius3.2[6] R
Temperature9000[6] K
Rotational velocity (v sin i)81[8] km/s
Other designations
BD+49°1150, GC 5174, HD 26961, HR 1324, HIP 20070, SAO 24531
Database references

b Persei (also known as HD 26961) is a spectroscopic triple star in the constellation Perseus. Its apparent magnitude is 4.60,[6] and it is about 320 light years away.[1]

In addition to the primary, an A-type giant, there is a smaller and cooler companion in a 1.53 day orbit, probably an F-class star around absolute magnitude 3.0, and a more distant companion in a 702-day orbit.[6]


  1. ^ a b c d e f Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry
  2. ^ a b 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. Bibcode:2009yCat....102025S.
  3. ^ Abt, Helmut A. (2009). "MK Classifications of Spectroscopic Binaries". The Astrophysical Journal Supplement. 180 (1): 117–18. Bibcode:2009ApJS..180..117A. doi:10.1088/0067-0049/180/1/117.
  4. ^ 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. Vizier catalog entry
  5. ^ Wilson, R. E. (1953). General Catalogue of Stellar Radial Velocities. Carnegie Institution for Science. Bibcode:1953GCRV..C......0W. LCCN 54001336.
  6. ^ a b c d e f Hill, G.; Aikman, G. C. L.; Cowley, A. P.; Bolton, C. T.; Thomas, J. C. (1976). "The radio-flaring triple system B Per". The Astrophysical Journal. 208: 152. Bibcode:1976ApJ...208..152H. doi:10.1086/154590.
  7. ^ ESA (1997). "The Hipparcos and Tycho Catalogues". VizieR On-line Data Catalog. 1239. Bibcode:1997yCat.1239....0E.
  8. ^ Royer, F. (2007). "Rotational velocities of A-type stars. III. Velocity distributions". Astronomy and Astrophysics. 463 (2): 671–682. arXiv:astro-ph/0610785. Bibcode:2007A&A...463..671R. doi:10.1051/0004-6361:20065224. S2CID 18475298.