HD 82785
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Antlia |
| Right ascension | 09h 33m 07.68032s[1] |
| Declination | −39° 07′ 44.6588″[1] |
| Apparent magnitude (V) | 6.43[2] |
| Characteristics | |
| Spectral type | F2IV/V[3] |
| B−V color index | +0.33[2] |
| Astrometry | |
| Radial velocity (Rv) | 27.76±0.48[1] km/s |
| Proper motion (μ) | RA: −41.698[1] mas/yr Dec.: 39.399[1] mas/yr |
| Parallax (π) | 13.5932 ± 0.0311 mas[1] |
| Distance | 239.9 ± 0.5 ly (73.6 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.06[4] |
| Details | |
| Mass | 1.68[5] M☉ |
| Radius | 2.43+0.04 −0.11[1] R☉ |
| Luminosity | 11.718+0.043 −0.042[1] L☉ |
| Surface gravity (log g) | 3.88[5] cgs |
| Temperature | 6,869[5] K |
| Metallicity [Fe/H] | –0.06[5] dex |
| Rotational velocity (v sin i) | 36[6] km/s |
| Age | 1.50[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 82785 is star in the southern constellation of Antlia. With an apparent visual magnitude of 6.43,[2] it is near the lower limit of visibility to the naked eye. The distance to this star, based on parallax measurements, is 240 light years. It is drifting further away from the Sun with a radial velocity of 28 km/s,[1] having come to within 142 light-years some 1.7 million years ago. It has an absolute magnitude of 2.06.[4]
This F-type star has a stellar classification of F2IV/V,[3] displaying a blended luminosity class of a main sequence star combined to a more evolved subgiant star. It is 1.5[5] billion years old and is spinning with a projected rotational velocity of 36 km/s.[6] The star has 1.68[5] times the mass and 2.43[1] times the radius of the Sun. HD 82785 is radiating 11.7[1] times the luminosity of the Sun from its photosphere at an effective temperature of 6,869 K.[5]
There is a magnitude 9.21 star positioned at an angular separation of 56.0″ along a position angle of 205° from the brighter component, as of 2016. This companion was first reported by W. S. Jacob in 1847.[7]
References
[edit]- ^ a b c d e f g h i j k 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.
- ^ a b c 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
- ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H
- ^ 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.
- ^ a b c d e f g h Casagrande, L.; et al. (2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey". Astronomy & Astrophysics. 530 (A138): 21. arXiv:1103.4651. Bibcode:2011A&A...530A.138C. doi:10.1051/0004-6361/201016276. S2CID 56118016.
- ^ a b Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298
- ^ 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.
