HD 129685

c2 Centauri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 14h 44m 59.20177s[1]
Declination −35° 11′ 30.5750″[1]
Apparent magnitude (V) +4.92[2]
Characteristics
Spectral type A0IVnn[3] or A0Vn[4]
B−V color index +0.013±0.006[2]
Astrometry
Radial velocity (Rv)−5.0±2.8[2] km/s
Proper motion (μ) RA: 9.255[1] mas/yr
Dec.: −3.943[1] mas/yr
Parallax (π)14.1199 ± 0.2091 mas[1]
Distance231 ± 3 ly
(71 ± 1 pc)
Absolute magnitude (MV)0.83[2]
Details
Mass2.10+0.12
−0.09
[5] M
Luminosity44.73[2] L
Surface gravity (log g)3.80±0.14[5] cgs
Temperature9,323[6] K
Age239+143
−144
[5] Myr
Other designations
c2 Cen, CD−34°9888, GC 19845, HD 129685, HIP 72104, HR 5489, SAO 205899[7]
Database references
SIMBADdata

HD 129685 is a single[8] star in the southern constellation of Centaurus. It is also known by its Bayer designation c2 Centauri, while HD 129685 is the star's identifier in the Henry Draper catalogue. This object has a white hue and is faintly visible to the naked eye with an apparent visual magnitude of +4.92.[2] It is located at a distance of approximately 231 light years from the Sun based on parallax, and it has an absolute magnitude of 0.83.[2] The star is drifting closer with a radial velocity of around −5 km/s.[2]

Two different stellar classifications have been reported for this star. A class of A0Vn[4] assigned by Abt and Morrell (1995) indicates it is a rapidly-rotating A-type main-sequence star, while a type of A0IVnn,[3] according to Gray and Garrison (1987), suggests it is a somewhat more evolved subgiant star. It is around 239 million years old with 2.1 times the mass of the Sun,[5] and is reported to be rotating close to its break-up velocity.[9] The star is radiating 45[2] times the luminosity of the Sun from its photosphere at an effective temperature of 9,323 K.[6]

References

  1. ^ 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. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e f g h i 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.
  3. ^ a b 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.
  4. ^ a b Abt, Helmut A.; Morrell, Nidia I. (July 1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement, 99: 135, Bibcode:1995ApJS...99..135A, doi:10.1086/192182.
  5. ^ a b c d Gullikson, Kevin; Kraus, Adam; Dodson-Robinson, Sarah (2016), "The Close Companion Mass-ratio Distribution of Intermediate-mass Stars", The Astronomical Journal, 152 (2): 40, arXiv:1604.06456, Bibcode:2016AJ....152...40G, doi:10.3847/0004-6256/152/2/40, S2CID 119179065.
  6. ^ a b di Benedetto, G. P. (November 1998), "Towards a fundamental calibration of stellar parameters of A, F, G, K dwarfs and giants", Astronomy and Astrophysics, 339: 858–871, Bibcode:1998A&A...339..858D.
  7. ^ "c02 Cen". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-03-03.
  8. ^ 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.
  9. ^ Molaro, P.; Morossi, C.; Ramella, M.; Franco, M. (July 1984), "IUE spectra of three A0 V stars rotating close to their break-up velocity: HD 119921, HD 129685, HD 181296", ESA Fourth European IUE Conf, 218: 223–225, Bibcode:1984ESASP.218..223M.