| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 07h 24m 08.46679s[1] |
| Declination | +40° 40′ 20.5980″[1] |
| Apparent magnitude (V) | 5.23[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[3] |
| Spectral type | K0.5 IIIa[4] |
| B−V color index | 1.249±0.003[2] |
| Astrometry | |
| Radial velocity (Rv) | +22.62±0.13[1] km/s |
| Proper motion (μ) | RA: −3.511[1] mas/yr Dec.: −20.935[1] mas/yr |
| Parallax (π) | 3.7070 ± 0.1684 mas[1] |
| Distance | 880 ± 40 ly (270 ± 10 pc) |
| Absolute magnitude (MV) | −2.58[2] |
| Details | |
| Mass | 5.05[3] M☉ |
| Radius | 48.05+1.66 −1.36[1] R☉ |
| Luminosity | 834.3±43.6[1] L☉ |
| Temperature | 4,475+65 −75[1] K |
| Metallicity [Fe/H] | 0.09±0.03[2] dex |
| Rotational velocity (v sin i) | 4.5[5] km/s |
| Age | 107[3] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
66 Aurigae is a single[7] star located approximately 880 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 magnitude of 5.23.[2] This object is moving further from the Earth with a heliocentric radial velocity of +22.6 km/s.[1]
At the age of 107 million years,[3] 66 Aurigae is an evolved giant star, most likely (98% chance) on the horizontal branch,[3] with a stellar classification of K0.5 IIIa.[4] Keenan and Yorka (1987) identified it as a strong–CN star, showing an excess strength of the blue CN bands in the spectrum.[8] Having exhausted the supply of hydrogen at its core, the star has expanded to 48[1] times the Sun's radius. 66 Aurigae has five[3] times the mass of the Sun and is radiating 834[1] times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,475 K.[1]
It was also known to be part of a much bigger constellation named Telescopium Herschelii before it was unrecognized by the International Astronomical Union (IAU).
GaiaDR2 was invoked but never defined (see the help page).Anderson2012 was invoked but never defined (see the help page).Stock2018 was invoked but never defined (see the help page).Keenan1989 was invoked but never defined (see the help page).DeMedeiros2000 was invoked but never defined (see the help page).SIMBAD was invoked but never defined (see the help page).Eggleton2008 was invoked but never defined (see the help page).Keenan1987 was invoked but never defined (see the help page).