Theta Volantis

Summary

Theta Volantis, Latinized from θ Volantis, is a solitary[9][10] star in the southern constellation of Volans. Based upon parallax measurements, is approximately 240 light years from the Sun. It has an apparent visual magnitude of 5.19,[2] which is bright enough to be faintly visible to the naked eye.

θ Volantis
Location of θ Volantis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Volans
Right ascension 08h 39m 05.16145s[1]
Declination −70° 23′ 12.2826″[1]
Apparent magnitude (V) 5.19[2]
Characteristics
Spectral type A0 V[3]
U−B color index −0.03[4]
B−V color index +0.01[4]
Astrometry
Radial velocity (Rv)13.00±4.2[2] km/s
Proper motion (μ) RA: +19.15[1] mas/yr
Dec.: −38.28[1] mas/yr
Parallax (π)13.58 ± 0.20 mas[1]
Distance240 ± 4 ly
(74 ± 1 pc)
Absolute magnitude (MV)+1.21[5]
Details
Mass2.3[6] M
Luminosity37[7] L
Surface gravity (log g)4.08[6] cgs
Temperature8,753[7] K
Rotational velocity (v sin i)98[6] km/s
Age185−364[6] Myr
Other designations
θ Vol, CPD−69°946, FK5 2683, HD 74405, HIP 42425, HR 3460, SAO 256535[8]
Database references
SIMBADdata

Theta Volantis is an A-type main sequence star with a stellar classification of A0 V[3] and a mass around 2.3 times that of the Sun. It is a young star with an estimated age of a few hundred million years, and is spinning rapidly with a projected rotational velocity of 98 km/s.[6] Theta Volantis shines 37 times as brightly as the Sun, with an effective temperature of 8,753 K in its outer atmosphere.[7]

The star has two optical companions: a magnitude 15.0 star at an angular separation of 22.10 along a position angle of 58°, and a magnitude 10.64 star at an angular separation of 41.3″ along a position angle of 105° (both as of 2000).[11]

References edit

  1. ^ a b c d e 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 Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
  3. ^ a b Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
  4. ^ a b Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
  5. ^ Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035, S2CID 119108982.
  6. ^ a b c d e 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.
  7. ^ a b c McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
  8. ^ "tet Vol -- Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-05.
  9. ^ 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.
  10. ^ De Rosa, R. J.; et al. (2013), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932, S2CID 88503488.
  11. ^ 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.