19 Cephei

19 Cep
Location of 19 Cephei (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Cepheus
Right ascension 22h 05m 08.78995s[1]
Declination +62° 16′ 47.3301″[1]
Apparent magnitude (V) 5.08[2]
Characteristics
Spectral type O9Ib[3]
U−B color index −0.91[2]
B−V color index +0.06[2]
Astrometry
Radial velocity (Rv)−12.8±0.9[4] km/s
Proper motion (μ) RA: −1.16[1] mas/yr
Dec.: −2.96[1] mas/yr
Parallax (π)1.58 ± 0.19 mas[1]
Distance1,200[5] pc
Absolute magnitude (MV)−5.45[6]
Details
Mass47[7] M☉
Radius17.0[3] R☉
Luminosity224,000[3] L☉
Surface gravity (log g)3.40±0.08[8] cgs
Temperature32,983±1,428[8] K
Metallicity [Fe/H]0.06±0.08[8] dex
Rotational velocity (v sin i)48[3] km/s
Other designations
19 Cep, BD+61°2246, HD 209975, HIP 109017, HR 8428, SAO 19849.
Database references
SIMBADdata

19 Cephei is a supergiant star in the northern circumpolar constellation of Cepheus. It has a spectral class of O9 and is a member of Cep OB2, an OB association of massive stars located about 615 parsecs (2,010 ly) from the Sun.

The spectrum of 19 Cephei shows line profile variability on an hourly and daily timescale. This is thought to be due to the changes in the stellar wind.[3]

Double star catalogues list several companions for 19 Cephei. The Washington Double Star Catalog describes four companions: 11th magnitude stars 20" and 56" away, and two 15th magnitude stars 4-5" away.[9] The Catalog of Components of Double and Multiple Stars gives only the two 11th magnitude stars.[10]

A scattered cluster of faint stars has been detected associated with 19 Cephei. The brightest likely members apart from 19 Cep itself are 10th magnitude stars.[11]

  1. ^ a b c d e Cite error: The named reference van Leeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference MERMILLIOD was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference martins was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Gontcharov was invoked but never defined (see the help page).
  5. ^ Aldoretta, E. J.; Caballero-Nieves, S. M.; Gies, D. R.; Nelan, E. P.; Wallace, D. J.; Hartkopf, W. I.; Henry, T. J.; Jao, W.-C.; Maíz Apellániz, J.; Mason, B. D.; Moffat, A. F. J.; Norris, R. P.; Richardson, N. D.; Williams, S. J. (2015). "The Multiplicity of Massive Stars: A High Angular Resolution Survey with the Guidance Sensor". The Astronomical Journal. 149 (1): 26. arXiv:1410.0021. Bibcode:2015AJ....149...26A. doi:10.1088/0004-6256/149/1/26. S2CID 58911264.
  6. ^ Puls, J.; Markova, N.; Scuderi, S.; Stanghellini, C.; Taranova, O. G.; Burnley, A. W.; Howarth, I. D. (2006). "Bright OB stars in the Galaxy. III. Constraints on the radial stratification of the clumping factor in hot star winds from a combined Hα, IR and radio analysis". Astronomy and Astrophysics. 454 (2): 625. arXiv:astro-ph/0604372. Bibcode:2006A&A...454..625P. doi:10.1051/0004-6361:20065073. S2CID 18271791.
  7. ^ Krticka, J.; Kubat, J. (2010). "Comoving frame models of hot star winds. I. Test of the Sobolev approximation in the case of pure line transitions". Astronomy and Astrophysics. 519: A50. arXiv:1005.0258. Bibcode:2010A&A...519A..50K. doi:10.1051/0004-6361/201014111. S2CID 118589169.
  8. ^ a b c Cite error: The named reference prugniel was invoked but never defined (see the help page).
  9. ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
  10. ^ 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.
  11. ^ Kharchenko, N. V.; Piskunov, A. E.; Röser, S.; Schilbach, E.; Scholz, R.-D. (2005). "109 new Galactic open clusters". Astronomy and Astrophysics. 440 (1): 403–408. arXiv:astro-ph/0505019. Bibcode:2005A&A...440..403K. doi:10.1051/0004-6361:20052740. S2CID 56292154.