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] |
| Distance | 232 ± 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 | |
| Mass | 1.30[2] M☉ |
| Radius | 19.86±0.89[8] R☉ |
| Luminosity | 127±11[8] L☉ |
| Surface gravity (log g) | 1.87[9] cgs |
| Temperature | 4,264±58[2] K |
| Metallicity [Fe/H] | −0.40[9] dex |
| Rotational velocity (v sin i) | 0.0[10] km/s |
| Age | 5.07[2] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
16 Aurigae is a triple star[12] 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,[13] 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,[14] 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 20 times the Sun's radius. The star is radiating 127[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″.[12] It shows a common proper motion with the primary and thus is a likely third member of the system.[6]
References
[edit]- ^ 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.
- ^ 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.
- ^ 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.
- ^ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- ^ 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 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.
- ^ 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.
- ^ a b c van Belle, Gerard T.; von Braun, Kaspar; Ciardi, David R.; Pilyavsky, Genady; Buckingham, Ryan S.; Boden, Andrew F.; Clark, Catherine A.; Hartman, Zachary; van Belle, Gerald; Bucknew, William; Cole, Gary (2021-12-01). "Direct Measurements of Giant Star Effective Temperatures and Linear Radii: Calibration against Spectral Types and V - K Color". The Astrophysical Journal. 922 (2): 163. arXiv:2107.09205. Bibcode:2021ApJ...922..163V. doi:10.3847/1538-4357/ac1687. ISSN 0004-637X.
- ^ 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.
- ^ 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.
- ^ "16 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-21.
- ^ 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.
- ^ 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.
- ^ 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.
