HD 34968

HD 34968
Location of HD 34968 (circled in red)
Observation data
Epoch J2000      Equinox J2000
Constellation Lepus[1]
Right ascension 05h 20m 26.91498s[2]
Declination −21° 14′ 23.1367″[2]
Apparent magnitude (V) 4.69 (4.73 + 8.45)[3]
Characteristics
Evolutionary stage main sequence[4]
Spectral type A0 V[5]
B−V color index −0.048±0.003[1]
Astrometry
Radial velocity (Rv)30.9±0.5[6] km/s
Proper motion (μ) RA: +17.149[2] mas/yr
Dec.: −9.382[2] mas/yr
Parallax (π)8.7188±0.1661 mas[2]
Distance374 ± 7 ly
(115 ± 2 pc)
Absolute magnitude (MV)−0.82[1]
Details
HD 34968 A
Mass2.6[7] M
Radius4.4[7] R
Luminosity177[7] L
Surface gravity (log g)3.56[7] cgs
Temperature10,046[7] K
Rotational velocity (v sin i)84[4] km/s
Other designations
BD−21°1135, HD 34968, HIP 24927, HR 1762, SAO 170327, WDS J05204-2114A[8]
Database references
SIMBADdata

HD 34968 is a binary star[3] system in the southern constellation Lepus. The combined apparent visual magnitude of 4.69[3] is bright enough to be visible to the naked eye. The distance to HD 34968 can be estimated from its annual parallax shift of 8.7 mas, yielding a range of 374 light years. It is moving further away from the Earth with a heliocentric radial velocity of 31 km/s,[6] having come within 118.6 ly some 3,686,000 years ago.[1]

The primary member, component A, is a magnitude 4.73 star. Houk and Smith-Moore (1978) gave this object a stellar classification of A0 V,[5] indicating it is an ordinary A-type main-sequence star. Gray and Garrison (1987) classified it as B9.5 III and noted that the spectrum is slightly variable.[9] It is 99.2%±2.6% of the way through its main sequence lifetime,[4] with 2.6 times the mass of the Sun and 4.4 times the Sun's radius.[7] The star is spinning with a projected rotational velocity of 84 km/s.[4] It is radiating 177 times the Sun's luminosity from its photosphere at an effective temperature of 10,046 K.[7]

The fainter secondary, component B, is a magnitude 8.45[3] star at an angular separation of 4.1 along a position angle of 279°, as of 2008.[10]

References

  1. ^ a b c d 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. XHIP record for this object at VizieR.
  2. ^ a b c d e 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.
  3. ^ a b c d 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.
  4. ^ a b c d Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  5. ^ a b Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
  6. ^ a b 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.
  7. ^ a b c d e f g Stassun, Keivan G.; et al. (2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467.
  8. ^ "HD 34968". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-26.
  9. ^ Gray, R. O.; Garrison, R. F. (December 1987), "The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation", Astrophysical Journal Supplement, 65: 581, Bibcode:1987ApJS...65..581G, doi:10.1086/191237.
  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