22 Orionis

This article is about o Orionis. Not to be confused with ο (omicron) Orionis.
22 Orionis
Location of 22 Orionis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Orion
Right ascension 05h 21m 45.74861s[1]
Declination 0° 22′ 56.9105″[1]
Apparent magnitude (V) 4.74[2]
Characteristics
Spectral type B2 IV-V[3][4]
U−B color index -0.79[2]
B−V color index -0.16[2]
Astrometry
Radial velocity (Rv)+28.80[5] km/s
Proper motion (μ) RA: −1.320[1] mas/yr
Dec.: +3.457[1] mas/yr
Parallax (π)2.8672 ± 0.3512 mas[1]
Distanceapprox. 1,100 ly
(approx. 350 pc)
Absolute magnitude (MV)−2.98[6]
Orbit[7]
Period (P)293 days
Eccentricity (e)0.15
Periastron epoch (T)2,442,175 JD
Argument of periastron (ω)
(secondary)		234°
Semi-amplitude (K1)
(primary)		4.1 km/s
Details
22 Ori A
Mass9.0[8] M☉
Luminosity741[9] L☉
Surface gravity (log g)3.56[10] cgs
Temperature19,953[9] K
Metallicity [Fe/H]−0.06[10] dex
Rotational velocity (v sin i)9[9] km/s
Age18.5[8] Myr
Other designations
o Orionis, 22 Ori, NSV 16291, BD−00°930, FK5 1147, GC 6579, HD 35039, HIP 25044, HR 1765, SAO 132028[11]
Database references
SIMBADdata

22 Orionis is a binary star[12] in the equatorial constellation of Orion. It has the Bayer designation o Orionis, while 22 Orionis is the Flamsteed designation. This system is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.74.[2] It is located approximately 1,100 light years away from the Sun based on parallax.[1] The system is moving further from the Earth with a heliocentric radial velocity of +28.80[5]

A light curves for 22 Orionis, adapted from Balona and Engelbrecht (1985)[13]

This is a single-lined spectroscopic binary with an orbital period of 293 days and an eccentricity of 0.15.[7] The visible member, component A, has a stellar classification of B2 IV-V,[3][4] matching a B-type star with a luminosity class that displays mixed traits of a main sequence star and a subgiant. It is a suspected Beta Cephei variable[14] or a slowly pulsating B star.[15] The star has nine[8] times the mass of the Sun and is radiating 741 times the Sun's luminosity[9] from its photosphere at an effective temperature of 19,953 K.[9]

  1. ^ a b c d e f 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. ^ a b c d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ a b van Belle, Gerard T.; von Braun, Kaspar (2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars". The Astrophysical Journal (abstract). 694 (2): 1085–1098. arXiv:0901.1206. Bibcode:2009ApJ...694.1085V. doi:10.1088/0004-637X/694/2/1085. S2CID 18370219.
  4. ^ a b Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H. 5050. Bibcode:1995yCat.5050....0H.
  5. ^ a b Wilson, R. E. (1953). "General Catalogue of Stellar Radial Velocities". Carnegie Institute Washington D.C. Publication. Carnegie Institution for Science. Bibcode:1953GCRV..C......0W. LCCN 54001336.
  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. S2CID 119257644. Vizier catalog entry
  7. ^ a b Abt, H. A.; Levy, S. G. (1978). "Binaries among B2-B5 IV, V absorption and emission stars". The Astrophysical Journal Supplement Series. 36: 241–258. Bibcode:1978ApJS...36..241A. doi:10.1086/190498.
  8. ^ a b c 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. S2CID 118629873. Vizier catalog entry
  9. ^ a b c d e Simón-Díaz, S.; Godart, M.; Castro, N.; Herrero, A.; Aerts, C.; Puls, J.; Telting, J.; Grassitelli, L. (2017). "The IACOB project . III. New observational clues to understand macroturbulent broadening in massive O- and B-type stars". Astronomy and Astrophysics. 597: A22. arXiv:1608.05508. Bibcode:2017A&A...597A..22S. doi:10.1051/0004-6361/201628541. S2CID 3478126. Vizier catalog entry
  10. ^ a b Soubiran, Caroline; Le Campion, Jean-François; Brouillet, Nathalie; Chemin, Laurent (2016). "The PASTEL catalogue: 2016 version". Astronomy & Astrophysics. 591: A118. arXiv:1605.07384. Bibcode:2016A&A...591A.118S. doi:10.1051/0004-6361/201628497. S2CID 119258214.
  11. ^ "22 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-09.
  12. ^ 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. S2CID 14878976.
  13. ^ Balona, L. A.; Engelbrecht, C. A. (June 1985). "Photometry and frequency analysis of line profile variables". Monthly Notices of the Royal Astronomical Society. 214 (4): 559–574. Bibcode:1985MNRAS.214..559B. doi:10.1093/mnras/214.4.559. Retrieved 30 September 2024.
  14. ^ 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.
  15. ^ Smith, M. A. (February 1980), "Nonradial m-mode changes in the 53 Persei variable 22 Orionis", Astrophysical Journal Supplement Series, 42: 261–281, Bibcode:1980ApJS...42..261S, doi:10.1086/190651