WW Aurigae
Binary star in the constellation Auriga
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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]
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| 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]