22 Orionis

22 Orionis
Location of 22 Orionis (circled)
Observation data
Epoch J2000      Equinox ICRS
Constellation Orion
Right ascension 05h 21m 45.74861s
Declination −00° 22′ 56.9105″
Apparent magnitude (V) 4.74
Characteristics
Spectral type B2 IV-V
U−B color index −0.79
B−V color index −0.16
Astrometry
Radial velocity (Rv)+28.80 km/s
Proper motion (μ) RA: −1.320 mas/yr
Dec.: +3.457 mas/yr
Parallax (π)2.8672±0.3512 mas
Distanceapprox. 1,100 ly
(approx. 350 pc)
Absolute magnitude (MV)−2.98
Orbit
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
Mass9.5 M☉
Radius6.6 R☉
Luminosity7,244 L☉
Surface gravity (log g)3.56 cgs
Temperature22,646 K
Metallicity [Fe/H]−0.06 dex
Rotation9.35 days
Rotational velocity (v sin i)9 km/s
Age18.5 Myr
Other designations
o Orionis, 22 Ori, NSV 16291, BD−00°930, FK5 1147, GC 6579, HD 35039, HIP 25044, HR 1765, SAO 132028
Database references
SIMBADdata

22 Orionis is a binary star 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. It is located approximately 1,100 light years away from the Sun based on parallax. The system is moving further from the Earth with a heliocentric radial velocity of +28.80

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

This is a single-lined spectroscopic binary with an orbital period of 293 days and an eccentricity of 0.15. The visible member, component A, has a stellar classification of B2 IV-V, 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 or a slowly pulsating B star. The star has about nine times the mass of the Sun and is radiating 7,244 times the Sun's luminosity from its photosphere at an effective temperature of 22,646 K.

References

  1. 1 2 3 4 5 6 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. 1 2 3 4 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. 1 2 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. 1 2 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. 1 2 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. 1 2 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. 1 2 3 4 Quintana, Alexis L.; Wright, Nicholas J.; Martínez García, Juan (2025). "A census of OB stars within 1 KPC and the star formation and core collapse supernova rates of the Milky Way". Monthly Notices of the Royal Astronomical Society. 538 (3): 1367. arXiv:2503.08286. Bibcode:2025MNRAS.538.1367Q. doi:10.1093/mnras/staf083.
  9. ↑ McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017). "Fundamental parameters and infrared excesses of Tycho-Gaia stars". Monthly Notices of the Royal Astronomical Society. 471 (1): 770. arXiv:1706.02208. Bibcode:2017MNRAS.471..770M. doi:10.1093/mnras/stx1433.
  10. 1 2 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. ↑ Oelkers, Ryan J.; Rodriguez, Joseph E.; Stassun, Keivan G.; Pepper, Joshua; Somers, Garrett; Kafka, Stella; Stevens, Daniel J.; Beatty, Thomas G.; Siverd, Robert J.; Lund, Michael B.; Kuhn, Rudolf B.; James, David; Gaudi, B. Scott (2018). "Variability Properties of Four Million Sources in the TESS Input Catalog Observed with the Kilodegree Extremely Little Telescope Survey". The Astronomical Journal. 155 (1): 39. arXiv:1711.03608. Bibcode:2018AJ....155...39O. doi:10.3847/1538-3881/aa9bf4.
  12. ↑ 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
  13. ↑ 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
  14. ↑ "22 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-09.
  15. ↑ 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.
  16. ↑ 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.
  17. ↑ 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.
  18. ↑ 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