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16 Aurigae
Observation data
Epoch J2000       Equinox J2000
Constellation Auriga
Right ascension 05h 18m 10.570s [1]
Declination +33° 22′ 17.81″ [1]
Apparent magnitude (V) 4.552 [2]
Characteristics
Spectral type K2.5 IIIb CN-0.5 [3]
U−B color index +1.26 [4]
B−V color index +1.276 [2]
Astrometry
Radial velocity (Rv)−28.44 [2] km/s
Proper motion (μ) RA: +31.63±0.53 [1]  mas/ yr
Dec.: −160.73±0.25 [1]  mas/ yr
Parallax (π)14.04 ± 0.58  mas [1]
Distance232 ± 10  ly
(71 ± 3  pc)
Absolute magnitude (MV)0.28 [5]
Orbit [6] [7]
Period (P)434.16±0.03 d
Semi-major axis (a)7.24±1.59  mas
Eccentricity (e)0.1189±0.0026
Inclination (i)52.93±9.46°
Longitude of the node (Ω)56.20±11.65°
Periastron epoch (T)2,448,348.1172±17.1872  JD
Argument of periastron (ω)
(secondary)
70.1±1.2°
Details
16 Aur A
Mass1.30 [2]  M
Radius18.8 [8]  R
Luminosity112 [8]  L
Surface gravity (log g)1.87 [9]  cgs
Temperature4,264±58 [2]  K
Metallicity [Fe/H]−0.40 [9]  dex
Rotational velocity (v sin i)0.0 [8] km/s
Age5.07 [2]  Gyr
Other designations
16 Aur, NSV 1909, BD+33°1000, HD 34334, HIP 24727, HR 1726, SAO 57853, PPM 70153, ADS 3872, WDS J05182+3322 [10]
Database references
SIMBAD data

16 Aurigae is a triple star [11] system located 232  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 visual magnitude of 4.547, [12] and is located about 2/3 of the way from Capella toward Beta Tauri. It also lies in the midst of the Melotte 31 cluster, but is merely a line-of-sight interloper. [6] The system has a relatively high proper motion, advancing across the celestial sphere at the rate of 0.166  arc seconds per annum, [13] and is moving closer to the Earth with a heliocentric radial velocity of −28 km/s. [2]

The primary component is a single-lined spectroscopic binary with an orbital period of 1.19 years and an eccentricity of 0.1189. [6] The visible member is an aging K-type giant star with a stellar classification of K2.5 IIIb CN-0.5; [3] sometimes just given as K3 III. The notation of the former class indicates weak lines of CN in the spectrum. [6] This star is an estimated five [2] billion years old with 1.30 [2] times the mass of the Sun. As a consequence of exhausting the hydrogen at its core, it has expanded to 18.8 [8] times the Sun's radius. The star is radiating 112 [8] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,264 K. [2]

A third component is an magnitude 10.6 star at an angular separation of 4.2 . [11] It shows a common proper motion with the primary and thus is a likely third member of the system. [6]

References

  1. ^ a b c d e van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv: 0708.1752. Bibcode: 2007A&A...474..653V. doi: 10.1051/0004-6361:20078357. S2CID  18759600.
  2. ^ a b c d e f g h i j Luck, R. Earle (2015). "Abundances in the Local Region. I. G and K Giants". The Astronomical Journal. 150 (3): 88. arXiv: 1507.01466. Bibcode: 2015AJ....150...88L. doi: 10.1088/0004-6256/150/3/88. S2CID  118505114.
  3. ^ a b Keenan, P.; McNeil, R. (October 1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245–266. Bibcode: 1989ApJS...71..245K. doi: 10.1086/191373.
  4. ^ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode: 1986EgUBV........0M.
  5. ^ 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.
  6. ^ a b c d e Griffin, R. F. (2008). "Spectroscopic binary orbits from photoelectric radial velocities - Paper 198: 48 Piscium, 16 Aurigae, 5 Herculis, and Beta Scuti". The Observatory. 128: 21–56. Bibcode: 2008Obs...128...21G.
  7. ^ Hartkopf, W. I.; et al. (June 30, 2006). "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 2017-08-01. Retrieved 2017-06-02.
  8. ^ a b c d e Massarotti, Alessandro; et al. (2008). "The Rotational and Radial Velocities for a Sample of 761 Hipparcos Giants and the Role of Binarity". The Astronomical Journal. 135 (1): 209–231. Bibcode: 2008AJ....135..209M. doi: 10.1088/0004-6256/135/1/209.
  9. ^ a b Matrozis, E.; et al. (November 2013). "Galactic chemical evolution of sulphur. Sulphur abundances from the [S i] λ1082 nm line in giants". Astronomy & Astrophysics. 559: 13. arXiv: 1309.0114. Bibcode: 2013A&A...559A.115M. doi: 10.1051/0004-6361/201322317. S2CID  118421435. A115.
  10. ^ "16 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-21.
  11. ^ a b 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.
  12. ^ Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode: 2000A&A...355L..27H.
  13. ^ Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal. 129 (3): 1483–1522. arXiv: astro-ph/0412070. Bibcode: 2005AJ....129.1483L. doi: 10.1086/427854. S2CID  2603568.

External links