Triple star system in the constellation Orion
32 Orionis
Location of 32 Orionis (circled)
Observation dataEpoch J2000 Equinox J2000
Constellation
Orion
Right ascension
05h 30m 47.05091s [ 1]
Declination
+05° 56′ 53.2925″[ 1]
Apparent magnitude (V)
4.20[ 2] (4.43 + 5.80) [ 3]
Characteristics
Spectral type
B5V + ? + B7V [ 3]
U−B color index
–0.56[ 2]
B−V color index
–0.13[ 2]
Astrometry Radial velocity (Rv )+18.60[ 4] km/s Proper motion (μ) RA: +5.10[ 1] mas /yr Dec.: –33.30[ 1] mas /yr Parallax (π)10.77 ± 0.64 mas [ 1] Distance 300 ± 20 ly (93 ± 6 pc ) Absolute magnitude (MV )–0.63[ 5]
Details 32 Ori A Mass 5.0[ 6] M ☉ Radius 2.9[ 7] R ☉ Luminosity 388[ 5] L ☉ Surface gravity (log g )4.40[ 8] cgs Temperature 16,020[ 9] K Rotational velocity (v sin i )169[ 8] km/s Age 65[ 8] Myr
Other designations A Ori ,
32 Ori ,
NSV 14617,
BD +05°939,
GC 6813,
HD 36267,
HIP 25813,
HR 1839,
SAO 112849,
CCDM J05308+0557AB,
WDS J05308+0557AB[ 10]
Database references SIMBAD data
32 Orionis is a triple[ 3] star system in the equatorial constellation of Orion . It has the Bayer designation A Orionis , while 32 Orionis is the Flamsteed designation . This system is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.20.[ 2] It is located approximately 303 light-years away from the Sun based on parallax ,[ 1] and is drifting further away with a radial velocity of +18.6 km/s.[ 4]
The system is a member of the eponymous 32 Orionis group , a young, nearby association of 46 co-moving stars first discovered in 2007.[ 11] Research in 2015 suggested that Bellatrix is a probable member of the group due to its distance and position in the sky and suggested it be called the Bellatrix Cluster,[ 12] although further research in 2017 called Bellatrix's membership into question due to its proper motion deviating significantly from the group.[ 11]
The primary component of this system is a B-type main-sequence star with a stellar classification of B5V[ 13] and a magnitude around 4.43. This is actually a spectroscopic binary with an orbital period of 3.964 days and eccentricity of 0.38.[ 3] The unseen companion has an estimated mass of 0.6 times that of the Sun .[ 14] Component B, at an angular separation of 1.08″ from the primary, is a class B7V star with a magnitude of 5.8, orbiting with the primary at a period of 614 years and eccentricity 0.22.[ 15]
References
^ 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
^ a b c d Ducati, J. R. (2002). "Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues . 2237 . Bibcode :2002yCat.2237....0D .
^ a b c d Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems" . Monthly Notices of the Royal Astronomical Society . 389 (2): 869–879. arXiv :0806.2878 . Bibcode :2008MNRAS.389..869E . doi :10.1111/j.1365-2966.2008.13596.x . S2CID 14878976 .
^ a b Kharchenko, N.V.; et al. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten . 328 (9): 889. arXiv :0705.0878 . Bibcode :2007AN....328..889K . doi :10.1002/asna.200710776 . S2CID 119323941 .
^ a b 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
^ Tetzlaff, N.; et al. (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
^ Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures". Astronomy and Astrophysics . 352 : 555–562. arXiv :astro-ph/9911002 . Bibcode :1999A&A...352..555A . Vizier catalog entry
^ a b c David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal . 804 (2): 146. arXiv :1501.03154 . Bibcode :2015ApJ...804..146D . doi :10.1088/0004-637X/804/2/146 . S2CID 33401607 . Vizier catalog entry
^ Zorec, J.; et al. (2009). "Fundamental parameters of B supergiants from the BCD system". Astronomy and Astrophysics . 501 (1): 297–320. arXiv :0903.5134 . Bibcode :2009A&A...501..297Z . doi :10.1051/0004-6361/200811147 . S2CID 14969137 .
^ "32 Ori" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-07-10 .
^ a b Bell, Cameron P. M.; et al. (June 2017). "A stellar census of the nearby, young 32 Orionis group" . Monthly Notices of the Royal Astronomical Society . 468 (1): 1198–1220. arXiv :1703.00015 . Bibcode :2017MNRAS.468.1198B . doi :10.1093/mnras/stx535 .
^ Bouy, H.; Alves, J. (2015-12-01). "Cosmography of OB stars in the solar neighbourhood" . Astronomy & Astrophysics . 584 : A26. doi :10.1051/0004-6361/201527058 . ISSN 0004-6361 .
^ Hoffleit, D.; Warren, W. H. (1995). "Bright Star Catalogue". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H . 5050 (5th ed.). Bibcode :1995yCat.5050....0H .
^ Tokovinin, A. (2008). "Comparative statistics and origin of triple and quadruple stars" . Monthly Notices of the Royal Astronomical Society . 389 (2): 925–938. arXiv :0806.3263 . Bibcode :2008MNRAS.389..925T . doi :10.1111/j.1365-2966.2008.13613.x . S2CID 16452670 .
^ Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical masses of a selected sample of orbital binaries" . Astronomy & Astrophysics . 546 : A69. Bibcode :2012A&A...546A..69M . doi :10.1051/0004-6361/201219774 . Vizier catalog entry