Star in the constellation Auriga
υ Aurigae Location of υ Aurigae (circled)
Observation dataEpoch J2000 Equinox J2000 Constellation Auriga Right ascension 05h 51m 02.43804s [ 1] Declination +37° 18′ 20.0581″[ 1] Apparent magnitude (V)4.74[ 2] Characteristics Evolutionary stage Asymptotic giant branch[ 3] Spectral type M0 III[ 4] U−Bcolor index +1.93[ 2] B−Vcolor index +1.62[ 2] R−Icolor index 1.07 Variable type Suspected[ 5] Astrometry Radial velocity (Rv )+37.68[ 6] km/s Proper motion (μ)RA: +35.914[ 1] mas /yr Dec.: −46.100[ 1] mas /yr Parallax (π)6.5040± 0.3305 mas [ 1] Distance 500 ± 30 ly pc ) Absolute magnitude (MV )−1.28[ 7] Details[ 8] Mass ± 0.22M ☉ Radius +8.7 R ☉ Luminosity ± 250L ☉ Surface gravity (log g )+0.04 [ 9] cgs Temperature ± 52K Age ± 0.68Gyr Other designations υ Aur ,31 Aurigae ,NSV 2661BD +37 1336FK5 2440HD 38944HIP 27639HR 2011SAO 58496[ 10] Database references SIMBAD data
Upsilon Aurigae ,Latinised from υ Aurigae, is theBayer designation for a single[ 11] star in thenorthern constellation ofAuriga . It has anapparent visual magnitude of 4.74,[ 2] parallax measurements, this star is approximately 500light-years (150parsecs ) distant from the Earth. It is drifting further away with aradial velocity of +38 km/s.[ 6]
This is anevolved red giant star with astellar classification of M0 III.[ 4] variable star [ 5] asymptotic giant branch , which means it is generating energy through thefusion of helium along a shell surrounding a small, inertcore of carbon and oxygen.[ 3] mass of the Sun and has expanded to 61 times theSun's radius . It is radiating 1,165 times theSun's luminosity from itsphotosphere at aneffective temperature ofK [ 8]
^a b c d e 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 atVizieR .^a b c d 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 Eggen, Olin J. (July 1992), "Asymptotic giant branch stars near the sun",Astronomical Journal ,104 (1):275– 313,Bibcode :1992AJ....104..275E ,doi :10.1086/116239 . ^a b Keenan, Philip C.; Barnbaum, Cecilia (June 1999), "Revision and Calibration of MK Luminosity Classes for Cool Giants by HIPPARCOS Parallaxes",The Astrophysical Journal ,518 (2):859– 865,Bibcode :1999ApJ...518..859K ,doi :10.1086/307311 S2CID 121902473 . ^a b Hamada, K.; et al. (January 1979), "On the Variability of upsilon Aurigae",Information Bulletin on Variable Stars ,1531 : 1,Bibcode :1979IBVS.1531....1H . ^a b Famaey, B.; et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters",Astronomy and Astrophysics ,430 (1):165– 186,arXiv :astro-ph/0409579 Bibcode :2005A&A...430..165F ,doi :10.1051/0004-6361:20041272 ,S2CID 17804304 . ^ 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 Baines, E.; et al. (2017), "Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer",The Astronomical Journal ,155 (1): 30,arXiv :1712.08109 Bibcode :2018AJ....155...30B ,doi :10.3847/1538-3881/aa9d8b S2CID 119427037 . ^ Takagi, Yuhei; et al. (June 2011), "Age Determinations of Early-M Type Pre-Main Sequence Stars Using a High-Resolution Near-Infrared Spectroscopic Method",Publications of the Astronomical Society of Japan ,63 (3):677– 684,Bibcode :2011PASJ...63..677T ,doi :10.1093/pasj/63.3.677 ^ "* ups Aur" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2012-08-23 .^ 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 .
