Astronomy:HD 70930

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Short description: Binary star system in the constellation Vela
HD 70930
Observation data
Equinox J2000.0]] (ICRS)
Constellation Vela
Right ascension  08h 22m 31.6941s[1]
Declination −48° 29′ 25.3631″[1]
Apparent magnitude (V) 4.79[2] (5.14 + 6.08)[3]
Characteristics
Spectral type B1V[4] or B2III[5]
B−V color index −0.146±0.002[2]
Astrometry
Radial velocity (Rv)+27.0±4.5[2] km/s
Proper motion (μ) RA: −5.10±0.39[1] mas/yr
Dec.: +7.76±0.33[1] mas/yr
Parallax (π)1.90 ± 0.32[1] mas
Distanceapprox. 1,700 ly
(approx. 530 pc)
Absolute magnitude (MV)−3.74[2]
Details
Mass15.6±0.8[4] M
Luminosity6,833.12[2] L
Rotational velocity (v sin i)169[6] km/s
Age10.0±0.1[4] Myr
Other designations
I 67[3], B Velorum, CD−48°3734, HD 70930, HIP 41039, HR 3294, SAO 219848, CCDM 08225-4829, WDS J08225-4829AB[7]
Database references
SIMBADdata

HD 70930 is a binary star[8] system in the southern constellation of Vela. It has the Bayer designation B Velorum, while HD 70930 is the star's identifier in the Henry Draper catalogue. With a combined apparent visual magnitude of 4.79,[2] it is visible to the naked eye as a faint point of light. The distance to this system is approximately 1,700 light years based on parallax,[1] and it has an absolute magnitude of −3.74.[2] It is drifting further away from the Sun with a radial velocity of about +27 km/s.[2] The system is a member of the Vel OB2 association of co-moving stars.[9]

The double nature of this system was discovered in 1896 by Scottish astronomer Robert T. A. Innes[3] – it is now known to be a double-lined spectroscopic binary.[10] The magnitude 5.14[3] primary component has a blue-white hue and has been assigned stellar classifications of B1V[4] and B2III,[5] matching a B-type main-sequence star or a giant star, respectively. It is a massive object – over 15 times the mass of the Sun – and is around 10 million years old.[4] The star has a high rate of spin, showing a projected rotational velocity of 169 km/s.[6] Its companion, at magnitude +6.08, is located at an angular separation of 0.8 along a position angle of 139°, as of 2008.[3]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. https://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html.  Vizier catalog entry
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 3.2 3.3 3.4 Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466, doi:10.1086/323920, Bibcode2001AJ....122.3466M 
  4. 4.0 4.1 4.2 4.3 4.4 Tetzlaff, N. et al. (January 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, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode2011MNRAS.410..190T. 
  5. 5.0 5.1 Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode1978mcts.book.....H. 
  6. 6.0 6.1 Uesugi, Akira; Fukuda, Ichiro (1970), "Catalogue of rotational velocities of the stars", Contributions from the Institute of Astrophysics and Kwasan Observatory (University of Kyoto), Bibcode1970crvs.book.....U. 
  7. "HD 70930". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+70930. 
  8. 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. doi:10.1111/j.1365-2966.2008.13596.x. Bibcode2008MNRAS.389..869E. 
  9. de Zeeuw, P. T. et al. (January 1999), "A HIPPARCOS Census of the Nearby OB Associations", The Astronomical Journal 117 (1): 354–399, doi:10.1086/300682, Bibcode1999AJ....117..354D. 
  10. Chini, R. et al. (2012), "A spectroscopic survey on the multiplicity of high-mass stars", Monthly Notices of the Royal Astronomical Society 424 (3): 1925–1929, doi:10.1111/j.1365-2966.2012.21317.x, Bibcode2012MNRAS.424.1925C.