18 Aurigae

18 Aurigae is a star located 233^[1] light years away from the Sun in the northern constellation of Auriga.^[9] The brightness of this object is near the limit of visibility to the naked eye under good viewing conditions, appearing as a dim, white-hued star with an apparent visual magnitude of 6.49.^[2] The star is moving away from the Sun with a heliocentric radial velocity of 7 km/s.^[6]

18 Aurigae

Observation data Epoch J2000      Equinox J2000
Constellation	Auriga
Right ascension	05h 19m 23.75342s[1]
Declination	+33° 59′ 07.4035″[1]
Apparent magnitude (V)	6.489[2]
Characteristics
Spectral type	A7 V[3]
U−B color index	+0.09[4]
B−V color index	+0.256±0.007[5]
Astrometry
Radial velocity (Rv)	7.3±2[6] km/s
Proper motion (μ)	RA: +28.497[1] mas/yr Dec.: −12.714[1] mas/yr
Parallax (π)	14.0275±0.0668 mas[1]
Distance	233 ± 1 ly (71.3 ± 0.3 pc)
Absolute magnitude (MV)	2.31[5]
Details
Mass	1.69±0.03[7] M☉
Radius	1.92+0.12 −0.03[1] R☉
Luminosity	10.091±0.063[1] L☉
Surface gravity (log g)	4.26±0.14 cgs
Temperature	7,432+231 −67[1] K
Rotational velocity (v sin i)	124[7] km/s
Age	950[8] Myr
Other designations
18 Aur, BD+33°1010, GC 6504, HD 34499, HIP 24832, HR 1734, SAO 57893, ADS 3893, WDS J05194+3359[9]
Database references
SIMBAD	data

This is an ordinary A-type main-sequence star with a stellar classification of A7 V,^[3] which indicates it is generating energy by hydrogen fusion at its core. The object is 950^[8] million years old with a high rate of spin, showing a projected rotational velocity of 124 km/s.^[7] It has 1.7^[7] times the mass of the Sun and 1.9^[1] times the Sun's radius. The star is radiating 10^[1] times the luminosity of the Sun from its photosphere at an effective temperature of 7,432 K.^[1]

18 Aurigae has a magnitude 12.50 companion star at an angular separation of 3.90″ along a position angle of 167°, as of 2006.^[10]