WW Aurigae

WW Aurigae is an eclipsing binary star system in the northern constellation of Auriga. It has a combined maximum apparent visual magnitude of 5.86,^[5] which is bright enough to be dimly visible to the naked eye. Based upon an annual parallax shift of 11.1 mas,^[2] it is located 293 light years from the Earth. The system is moving further away with a heliocentric radial velocity of −9 km/s, having come to within 212.5 ly some 3.12 million years ago.^[3]

WW Aurigae

A light curve for WW Aurigae, plotted from Hiparcos data[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Auriga
Right ascension	06h 32m 27.18477s[2]
Declination	+32° 27′ 17.6324″[2]
Apparent magnitude (V)	5.82[3]
Characteristics
Spectral type	A4m + A5m[4]
B−V color index	0.188±0.007[3]
Variable type	EA[5]
Astrometry
Radial velocity (Rv)	−8.7±0.9[3] km/s
Proper motion (μ)	RA: −26.3507[2] mas/yr Dec.: −17.343[2] mas/yr
Parallax (π)	11.1431±0.0691 mas[2]
Distance	293 ± 2 ly (89.7 ± 0.6 pc)
Absolute magnitude (MV)	1.29[3]
Orbit[6]
Period (P)	2.525 d
Eccentricity (e)	0.00
Periastron epoch (T)	2,432,945.539±1.0 JD
Argument of periastron (ω) (secondary)	0.00°
Semi-amplitude (K1) (primary)	115.6 km/s
Semi-amplitude (K2) (secondary)	127.7 km/s
Details[7]
WW Aur A
Mass	1.964±0.007 M☉
Radius	1.980±0.009 R☉
Luminosity	13.5[8] L☉
Surface gravity (log g)	4.160±0.007 cgs
Temperature	8,350±200 K
Rotational velocity (v sin i)	35±10 km/s
Age	565±15 Myr
WW Aur B
Mass	1.814±0.007 M☉
Radius	1.807±0.009 R☉
Luminosity	10.5[8] L☉
Surface gravity (log g)	4.165±0.007 cgs
Temperature	8,170±300 K
Rotational velocity (v sin i)	55±10[7] km/s
Other designations
WW Aur, BD+32°1324, FK5 2500, HD 46052, HIP 31173, HR 2372, SAO 59194[9]
Database references
SIMBAD	data

This is a double-lined^[4] spectroscopic binary system, having a circular orbit with a period of 2.5 days.^[6] It was discovered to be variable independently by Friedrich Schwab^[10] and Heinrich Van Solowiew in 1918.^[11] It was given its variable star designation in 1919.^[12] Both components are metallic-lined, or Am stars, with a spectrum showing a deficiency of calcium and scandium, and an overabundance of heavier elements.^[13] Together they form an EA, or Algol-type, eclipsing binary with the primary occultation reducing the net magnitude to a minimum of 6.54 and the secondary eclipse lowering it to 6.43, over a cycle time of 2.52501936 days.^[5]