HD 192685

HD 192685, also known as QR Vul or HR 7739, is a Be star 1,199 ly away in the Vulpecula constellation. It is visible to the naked eye.

HD 192685
Location of HD 192685 (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Vulpecula
Right ascension  20h 15m 15.89542s[1]
Declination 25° 35′ 31.0549″[1]
Apparent magnitude (V) 4.60 - 4.80[2]
Characteristics
Spectral type B3V[3]
U−B color index -0.73[4]
B−V color index -0.18[4]
Variable type γ Cas[2]
Astrometry
Radial velocity (Rv)-7.00[5] km/s
Proper motion (μ) RA: +6.93[1] mas/yr
Dec.: -3.89[1] mas/yr
Parallax (π)3.29 ± 0.51[1] mas
Distanceapprox. 1,000 ly
(approx. 300 pc)
Absolute magnitude (MV)-2.56[6]
Details
Mass8.0[7] M☉
Luminosity3331[6] L☉
Surface gravity (log g)3.49[8] cgs
Temperature18,700[9] K
Metallicity [Fe/H]-0.10[8] dex
Rotational velocity (v sin i)160[10] km/s
Other designations
BD+25° 4165, CCDM J20153+2536AB, GC 28140, HIP 99824, HR 7739, HD 192685, SAO 88410, WDS J20153+2536AB
Database references
SIMBADdata

Description

HD 192685 varies slightly in brightness and is classified as a γ Cassiopeiae variable.[2]

From October to December 1982 the Hydrogen alpha absorption line increased in emission strength by 30%.[11] The line is partially filled by redshifted emission.[12]

HD 192685 has excess infrared emissions (12-100 μm) which are interpreted to be free-free radiation in the gas surrounding the star.[13]

Companions

It has at least one companion with separation 0.55" and magnitude 7.55,[14] and may also be a long-period spectroscopic binary.[15]

References
  1. 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. Vizier catalog entry
  2. 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. Walker, G. A. H.; Yang, S.; Witt, A. N.; Fahlman, G. G. (Aug–Sep 1980). "The extinction of HD 200775 by dust in NGC 7023". Publications of the Astronomical Society of the Pacific. 92: 414. Bibcode:1980PASP...92..411W. doi:10.1086/130687.
  4. Mermilliod, J. C. (2006). "VizieR Online Data Catalog: Homogeneous Means in the UBV System (Mermilliod 1991)". VizieR On-line Data Catalog: II/168. Originally Published in: Institut d'Astronomie. 2168. Bibcode:2006yCat.2168....0M.Vizier catalog entry
  5. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
  6. 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. Vizier catalog entry
  7. Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. Vizier catalog entry
  8. Wu, Yue; Singh, H. P.; Prugniel, P.; Gupta, R.; Koleva, M. (2010). "Coudé-feed stellar spectral library – atmospheric parameters". Astronomy & Astrophysics. 525: A71. arXiv:1009.1491. Bibcode:2011A&A...525A..71W. doi:10.1051/0004-6361/201015014.
  9. Hohle, M.M.; Neuhäuser, R.; Schutz, B.F. (2010). "Masses and luminosities of O- and B-type stars and red supergiants". Astronomische Nachrichten. 331 (4): 349. arXiv:1003.2335. Bibcode:2010AN....331..349H. doi:10.1002/asna.200911355. Vizier catalog entry
  10. Abt, Helmut A.; Levato, Hugo; Grosso, Monica (2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573 (1): 359–365. Bibcode:2002ApJ...573..359A. doi:10.1086/340590.
  11. Pavlovski, K.; Bozic, H.; Harmanec, P.; Horn, J.; Koubsky, P. (14 November 1983). "Sudden Brightening of the Recently Discovered Be Star HR 7739". Information Bulletin on Variable Stars. 2431 (1): 1. Bibcode:1983IBVS.2431....1P. ISSN 0374-0676.
  12. Green, Daniel W. E. (July 14, 1982). "2 Vul AND HR 7739". IAU Circular. IAU Central Bureau for Astronomical Telegrams. 3710. Retrieved 11 December 2012.
  13. Cote, J. (July 1987). "B and A type stars with unexpectedly large colour excesses at IRAS wavelengths". Astronomy and Astrophysics. 181 (1): 83. Bibcode:1987A&A...181...77C. ISSN 0004-6361.
  14. Eggleton, P. P.; Tokovinin, A. A. (2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. Vizier catalog entry
  15. 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. Vizier catalog entry
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