Psi8 Aurigae

Psi⁸ Aurigae is a star in the northern constellation of Auriga. Its name is a Bayer designation that is Latinized from ψ⁸ Aurigae, and abbreviated Psi⁸ Aur or ψ⁸ Aur. This star is just visible to the naked eye with an apparent visual magnitude of 6.443. Based upon parallax measurements,^[2] it is approximately 667 light-years (205 parsecs) distant from the Earth. It is receding from the Sun with a radial velocity of 27 km/s.^[1]

For other stars with this Bayer designation, see ψ Aurigae.

Psi⁸ Aurigae

Location of ψ8 Aurigae (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Auriga[1]
Right ascension	06h 53m 57.073s[2]
Declination	+38° 30′ 18.07″[2]
Apparent magnitude (V)	6.46[1]
Characteristics
Spectral type	B9.5p[3]
Apparent magnitude (J)	6.471±0.034[4]
Apparent magnitude (H)	6.532±0.036[4]
Apparent magnitude (K)	6.514±0.018[4]
B−V color index	−0.044±0.007[1]
Variable type	Constant[1]
Astrometry
Radial velocity (Rv)	27.1±1.0[1] km/s
Proper motion (μ)	RA: −1.307 mas/yr[2] Dec.: −27.406 mas/yr[2]
Parallax (π)	4.8897±0.0602 mas[2]
Distance	667 ± 8 ly (205 ± 3 pc)
Absolute magnitude (MV)	−0.31[1]
Details
Mass	2.0[5] M☉
Radius	3.1[5] R☉
Luminosity	100[5] L☉
Surface gravity (log g)	3.68[5] cgs
Temperature	10,200[5] K
Metallicity [Fe/H]	−0.161[6] dex
Rotational velocity (v sin i)	40±9[7] km/s
Age	234[5] Myr
Other designations
ψ8 Aurigae, 61 Aurigae, BD+38°1638, HD 50204, HIP 33133, HR 2547, SAO 59589[8]
Database references
SIMBAD	data

The spectrum of the star has a stellar classification of B9.5p, matching a very late B-type star with unspecified luminosity class. The "p" indicates a peculiarity in the spectrum.^[3] φ⁸ Aurigae has been reported to be an Ap star with unusually string silicon lines in its spectrum, or a mercury-manganese star,^[9] but it is now considered doubtful whether it is actually a chemically peculiar star.^[10]

This star has double the mass of the Sun and more than triple the Sun's radius. It is an estimated 234^[5] million years old and is spinning with a projected rotational velocity of 40 km/s.^[7] The star is radiating 100 times the luminosity of the Sun from its photosphere at an effective temperature of 10,200 K.^[5]