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66 Aurigae

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66 Aurigae
Observation data
Epoch J2000      Equinox J2000
Constellation Auriga
Right ascension 07h 24m 08.46679s[1]
Declination +40° 40′ 20.5980″[1]
Apparent magnitude (V) 5.23[2]
Characteristics
Evolutionary stage horizontal branch[3]
Spectral type K0.5 IIIa[4]
B−V color index 1.249±0.003[2]
Astrometry
Radial velocity (Rv)+22.62±0.13[1] km/s
Proper motion (μ) RA: −3.511[1] mas/yr
Dec.: −20.935[1] mas/yr
Parallax (π)3.7070 ± 0.1684 mas[1]
Distance880 ± 40 ly
(270 ± 10 pc)
Absolute magnitude (MV)−2.58[2]
Details
Mass5.05[3] M
Radius48.05+1.66
−1.36
[1] R
Luminosity834.3±43.6[1] L
Temperature4,475+65
−75
[1] K
Metallicity [Fe/H]0.09±0.03[2] dex
Rotational velocity (v sin i)4.5[5] km/s
Age107[3] Myr
Other designations
66 Aur, BD+40°1852, FK5 1191, GC 9850, HD 57669, HIP 35907, HR 2805, SAO 41738[6]
Database references
SIMBADdata

66 Aurigae is a single[7] star located approximately 880 light years away from the Sun in the northern constellation of Auriga. It is visible to the naked eye as a faint, orange hued star with an apparent magnitude of 5.23.[2] This object is moving further from the Earth with a heliocentric radial velocity of +22.6 km/s.[1]

At the age of 107 million years,[3] 66 Aurigae is an evolved giant star, most likely (98% chance) on the horizontal branch,[3] with a stellar classification of K0.5 IIIa.[4] Keenan and Yorka (1987) identified it as a strong–CN star, showing an excess strength of the blue CN bands in the spectrum.[8] Having exhausted the supply of hydrogen at its core, the star has expanded to 48[1] times the Sun's radius. 66 Aurigae has five[3] times the mass of the Sun and is radiating 834[1] times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,475 K.[1]

It was also known to be part of a much bigger constellation named Telescopium Herschelii before it was unrecognized by the International Astronomical Union (IAU).

References

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  1. ^ a b c d e f g h i j k l m 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 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 c d e f Stock, S.; et al. (August 2018), "Precise radial velocities of giant stars. X. Bayesian stellar parameters and evolutionary stages for 372 giant stars from the Lick planet search", Astronomy & Astrophysics, 616: 15, arXiv:1805.04094, Bibcode:2018A&A...616A..33S, doi:10.1051/0004-6361/201833111, S2CID 119361866, A33.
  4. ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins Catalog of Revised MK Types for the Cooler Stars", The Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
  5. ^ De Medeiros, J. R.; et al. (November 2000), "Rotation and lithium in single giant stars", Astronomy and Astrophysics, 363: 239–243, arXiv:astro-ph/0010273, Bibcode:2000A&A...363..239D.
  6. ^ "66 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-24.
  7. ^ 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.
  8. ^ Keenan, Philip C.; et al. (July 1987), "Recognition and classification of strong-CN giants", Publications of the Astronomical Society of the Pacific, 99: 629–636, Bibcode:1987PASP...99..629K, doi:10.1086/132025.
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