47 Aurigae

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
47 Aurigae
Observation data
Epoch J2000      Equinox J2000
Constellation Auriga
Right ascension  06h 30m 02.97400s[1]
Declination +46° 41′ 08.0041″[1]
Apparent magnitude (V) 5.88[2]
Evolutionary stage giant
Spectral type K4 III[3]
B−V color index 1.448±0.008[2]
Radial velocity (Rv)−48.32±0.20[2] km/s
Proper motion (μ) RA: −7.582[1] mas/yr
Dec.: +7.854[1] mas/yr
Parallax (π)4.7747 ± 0.0978[1] mas
Distance680 ± 10 ly
(209 ± 4 pc)
Absolute magnitude (MV)−0.47[2]
Mass1.40±0.41[4] M
[1] R
Luminosity357.7±8.9[1] L
Surface gravity (log g)1.57±0.11[4] cgs
Temperature4,157±92[4] K
Metallicity [Fe/H]−0.218±0.093[5] dex
[4] Gyr
Other designations
47 Aur, BD+46°1149, FK5 2496, HD 45466, HIP 30972, HR 2338, SAO 41130[6]
Database references

47 Aurigae is a star located around 680 light years away from the Sun in the northern constellation of Auriga. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.88.[2] This object is moving closer to the Earth with a heliocentric radial velocity of −48 km/s, and is expected to come to within 111 ly in around 3.6 million years.[2]

This object is an aging giant star with a stellar classification of K4 III,[3] having exhausted the hydrogen supply at its core then expanded to 36[1] times the Sun's radius, it is roughly two[4] billion years old with 1.4[4] times the mass of the Sun. The star is radiating 358[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,157 K.[4]


  1. ^ a b c d e f g h i 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 f 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.
  3. ^ a b Adams, Walter S.; et al. (1935), "The Spectroscopic Absolute Magnitudes and Parallaxes of 4179 Stars", Astrophysical Journal, 81: 187, Bibcode:1935ApJ....81..187A, doi:10.1086/143628
  4. ^ a b c d e f g Feuillet, Diane K.; et al. (2016), "Determining Ages of APOGEE Giants with Known Distances", The Astrophysical Journal, 817: 40, arXiv:1511.04088, Bibcode:2016ApJ...817...40F, doi:10.3847/0004-637X/817/1/40.
  5. ^ Taylor, B. J. (February 1999), "Catalogs of temperatures and [Fe/H] averages for evolved G and K stars", Astronomy and Astrophysics Supplement, 134: 523–524, Bibcode:1999A&AS..134..523T, doi:10.1051/aas:1999153.
  6. ^ "47 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-23.