Kappa Aurigae

κ Aurigae

Location of κ Aurigae (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Auriga
Right ascension	06^h 15^m 22.68906^s[1]
Declination	+29° 29′ 53.0760″[1]
Apparent magnitude (V)	4.335[2]
Characteristics
Evolutionary stage	horizontal branch[3]
Spectral type	G8.5 IIIb[4]
U−B color index	+0.812[2]
B−V color index	+1.023[2]
R−I color index	0.54
Astrometry
Radial velocity (Rv)	+20.69 ± 0.15[5] km/s
Proper motion (μ)	RA: −70.88[1] mas/yr Dec.: −261.42[1] mas/yr
Parallax (π)	18.43 ± 0.23 mas[1]
Distance	177 ± 2 ly (54.3 ± 0.7 pc)
Absolute magnitude (MV)	+0.65[6]
Details
Mass	1.25[7] M☉
Radius	11[5] R☉
Luminosity	54[5] L☉
Surface gravity (log g)	2.7[5] cgs
Temperature	4,732[5] K
Metallicity [Fe/H]	−0.33[5] dex
Rotational velocity (v sin i)	2.5[5] km/s
Age	5.59[7] Gyr
Other designations
κ Aur, 44 Aurigae, BD+29°1154, FK5 1168, HD 43039, HIP 29696, HR 2219, SAO 78143, 2MASS J06152269+2929535, Gaia DR2 3436911415279548032[8]
Database references
SIMBAD	data

Kappa Aurigae, Latinised from κ Aurigae, is the Bayer designation for a star in the northern constellation of Auriga. It is visible to the naked eye with an apparent visual magnitude of 4.3.^[2] Based upon an annual parallax shift of 18.43 mas,^[1] it is approximately 177 light-years (54 parsecs) distant from Earth.

This is an evolved giant star with a stellar classification of G8.5 IIIb.^[4] It is a red clump star, which means it is towards the cool end of the horizontal branch and is generating energy through the fusion of helium at its core.^[3] Kappa Aurigae has expanded to 11 times the radius of the Sun and shines with 54 times the Sun's luminosity. This energy is radiated into outer space from the outer envelope at an effective temperature of 4,732 K.^[5] At this heat, the star glows with the orange hue of a G-type star.^[9]

References

1. van Leeuwen, F. (November 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. Jennens, P. A.; Helfer, H. L. (September 1975), "A new photometric metal abundance and luminosity calibration for field G and K giants", Monthly Notices of the Royal Astronomical Society, 172 (3): 667–679, Bibcode:1975MNRAS.172..667J, doi:10.1093/mnras/172.3.667.
3. Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.
4. 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.
5. Massarotti, Alessandro; et al. (January 2008), "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, S2CID 121883397.
6. 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.
7. 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.
8. "* kap Aur". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-18.
9. "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on February 22, 2012, retrieved 2012-01-16.

References

• HR 2219
• Image Kappa Aurigae