Omega Lupi

Omega Lupi
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Lupus
Right ascension 15h 38m 03.20372s[1]
Declination −42° 34′ 02.4444″[1]
Apparent magnitude (V) 4.33[2] (4.33 + 11.0)[3]
Characteristics
Spectral type K4.5 III[4]
U−B color index +1.72[2]
B−V color index +1.43[2]
Astrometry
Radial velocity (Rv)−6.8±2.7[5] km/s
Proper motion (μ) RA: −21.37[1] mas/yr
Dec.: −29.98[1] mas/yr
Parallax (π)8.97 ± 0.27 mas[1]
Distance360 ± 10 ly
(111 ± 3 pc)
Absolute magnitude (MV)+0.21[6]
Details
Radius40[7] R☉
Luminosity167[6] L☉
Other designations
ω Lup, CD−42° 10601, FK5 3232, HD 139127, HIP 76552, HR 5797, SAO 226004.[8]
Database references
SIMBADdata

Omega Lupi, Latinised from ω Lupi, is a double star in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 4.33,[2] showing up as a red-hued star just to the south of Gamma Lupi.[9] Based upon an annual parallax shift of 8.97[1] mas as seen from Earth, it is located around 360 light-years from the Sun.

As of 2007, the components of this system had an angular separation of 11.4 arcseconds along a position angle of 29°,[10] and are most likely gravitationally bound as a wide binary star system.[3] The primary component is a magnitude 4.48 evolved giant star with a stellar classification of K4.5 III.[4] The measured angular diameter, after correction for limb darkening, is 3.39±0.04 mas.[11] At the estimated distance of Omega Lupi, this yields a physical size of about 40 times the radius of the Sun.[7] The companion is a magnitude 11.0 star.[3]

References

  1. ^ 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.
  2. ^ a b c d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
  3. ^ a b c 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.
  4. ^ a b Landi Dessy, J.; Keenan, P. C. (November 1966), "Spectral Types on the MK System for Forty-Three Bright Southern Stars, K2-M6", Astrophysical Journal, 146: 587, Bibcode:1966ApJ...146..587L, doi:10.1086/148925.
  5. ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
  6. ^ 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.
  7. ^ a b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R*) is given by:
  8. ^ "ome Lup". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-03-10.
  9. ^ Arnold, H.J.P; et al. (1999), The Photographic Atlas of the Stars, CRC Press, p. 176, ISBN 0750306548.
  10. ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.
  11. ^ Richichi, A.; et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics, 431 (2): 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039.