HD 34968 is a binary star[2] system in the southern constellation Lepus. The combined apparent visual magnitude of 4.69[2] 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,[5] having come within 118.6 ly some 3,686,000 years ago.[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lepus |
| Right ascension | 05h 20m 26.91498s[1] |
| Declination | −21° 14′ 23.1367″[1] |
| Apparent magnitude (V) | 4.69 (4.73 + 8.45)[2] |
| Characteristics | |
| Spectral type | A0 V[3] |
| B−V color index | −0.048±0.003[4] |
| Astrometry | |
| Radial velocity (Rv) | 30.9±0.5[5] km/s |
| Proper motion (μ) | RA: +17.149[1] mas/yr Dec.: −9.382[1] mas/yr |
| Parallax (π) | 8.7188 ± 0.1661 mas[1] |
| Distance | 374 ± 7 ly (115 ± 2 pc) |
| Absolute magnitude (MV) | −0.82[4] |
| Details | |
| HD 34968 A | |
| Mass | 3.34±0.06[6] M☉ |
| Radius | 2.0[7] R☉ |
| Luminosity | 245+38 −33[6] L☉ |
| Temperature | 10,046+70 −69[6] K |
| Rotational velocity (v sin i) | 84[6] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
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,[3] 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,[6] with 3.34[6] times the mass of the Sun and 2.0[7] times the Sun's radius. The star is spinning with a projected rotational velocity of 84 km/s.[6] It is radiating 245[6] times the Sun's luminosity from its photosphere at an effective temperature of 10,046 [6]
The fainter secondary, component B, is a magnitude 8.45[2] star at an angular separation of 4.1″ along a position angle of 279°, as of 2008.[10]
References
edit- ^ 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.
- ^ 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.
- ^ 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.
- ^ a b c 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.
- ^ 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.
- ^ a b c d e f g h i 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.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics, 367 (2): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ "HD 34968". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-26.
- ^ 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.
- ^ 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