LY Aurigae
LY Aurigae is the bright star, with the red arrow pointing at it, in the southeast corner of this picture of Messier 38 | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 05h 29m 42.650s |
| Declination | +35° 22′ 30.09″ |
| Apparent magnitude (V) | 6.85 (6.66 - 7.35) |
| Characteristics | |
| Spectral type | O9II + O9III + B0.5III |
| U−B color index | −0.78 |
| B−V color index | +0.20 |
| Variable type | β Lyr |
| Astrometry | |
| Radial velocity (Rv) | 5.40 km/s |
| Proper motion (μ) | RA: −0.20±3.19 mas/yr Dec.: −1.17±2.07 mas/yr |
| Parallax (π) | 3.28±2.40 mas |
| Distance | 6,800 ly (2,090 pc) |
| Absolute magnitude (MV) | −5.62 + −5.11 + −4.43 |
| Orbit | |
| Primary | Aa |
| Companion | Ab |
| Period (P) | 4.0025 days |
| Semi-major axis (a) | 36.1 R☉ |
| Eccentricity (e) | 0.0 |
| Inclination (i) | 87.7° |
| Semi-amplitude (K1) (primary) | 161.9 km/s |
| Semi-amplitude (K2) (secondary) | 294.3 km/s |
| Orbit | |
| Primary | Ba |
| Companion | Bb |
| Period (P) | 20.4642 days |
| Eccentricity (e) | 0.246 |
| Semi-amplitude (K1) (primary) | 33.0 km/s |
| Details | |
| Aa | |
| Mass | 25.5 M☉ |
| Radius | 16.1 R☉ |
| Luminosity | 214,000 L☉ |
| Surface gravity (log g) | 3.425 cgs |
| Temperature | 31,000 K |
| Rotational velocity (v sin i) | 194 km/s |
| Ab | |
| Mass | 14.0 M☉ |
| Radius | 12.6 R☉ |
| Luminosity | 135,000 L☉ |
| Surface gravity (log g) | 3.378 cgs |
| Temperature | 31,150 K |
| Rotational velocity (v sin i) | 152 km/s |
| B | |
| Luminosity | 47,000 L☉ |
| Surface gravity (log g) | 4.00 cgs |
| Temperature | 26,000 K |
| Rotational velocity (v sin i) | 30 km/s |
| Age | 5 Myr |
| Other designations | |
| LY Aurigae, BD+35°1137, HD 35921, SAO 58105, HIP 25733, WDS J05297+3523, AAVSO 0523+35 | |
| Database references | |
| SIMBAD | data |
LY Aurigae is a multiple star system in the constellation Auriga. It is an eclipsing binary variable star, dropping in brightness by 0.7 magnitudes every 4 days. The system is around 6,800 light years away in the Auriga OB1 stellar association.