Chi Aurigae
Binary star system in the constellation Auriga / From Wikipedia, the free encyclopedia
Chi Aurigae, Latinized from χ Aurigae, is the Bayer designation for a binary star system in the northern constellation of Auriga. It is faintly visible to the naked eye with an apparent visual magnitude of 4.74.[2] The annual parallax shift of this object is much smaller than the measurement error, making distance estimates by that means unreliable.[1] The estimated distance to this star is approximately 3,000 light years. The brightness of the star is diminished by 1.26 in magnitude from extinction caused by intervening gas and dust.[5]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Auriga |
Right ascension | 05h 32m 43.67312s[1] |
Declination | +32° 11′ 31.2753″[1] |
Apparent magnitude (V) | 4.74[2] |
Characteristics | |
Spectral type | B5 Iab[3] |
U−B color index | –0.44[2] |
B−V color index | +0.32[2] |
Astrometry | |
Radial velocity (Rv) | –0.2[4] km/s |
Proper motion (μ) | RA: –1.52[1] mas/yr Dec.: –4.33[1] mas/yr |
Distance | 3,000 ly (912[5] pc) |
Absolute magnitude (MV) | –6.4[5] |
Orbit[5] | |
Period (P) | 676.85 ± 0.21 d |
Eccentricity (e) | 0.116 ± 0.048 |
Longitude of the node (Ω) | 181.7° ± 24.3° |
Periastron epoch (T) | 2422754.2 ± 46.1 HJD |
Semi-amplitude (K1) (primary) | 22.0 ± 2.9 km/s |
Details | |
Surface gravity (log g) | 2.5[5] cgs |
Temperature | 15,500[6] K |
Rotational velocity (v sin i) | 40[7] km/s |
Other designations | |
Database references | |
SIMBAD | data |
Chi Aurigae is a spectroscopic binary with an orbital period of 676.85 d and an eccentricity of 0.12.[9] The primary component of this system is a supergiant star with a stellar classification of B5 Iab.[3] It has a stellar wind that is causing mass loss at the rate of 0.38–0.46 × 10−9 solar masses per year, or the equivalent of the Sun's mass every 2.4 billion years.[6]