26 Aurigae

26 Aurigae
Observation data
Epoch J2000      Equinox J2000
Constellation Auriga
Right ascension 05h 38m 38.08510s
Declination +30° 29 32.7054
Apparent magnitude (V) 5.406 (6.29 / 6.21)
Characteristics
Spectral type G8III + A1IV or B9.5V
U−B color index +0.25
B−V color index +0.45
Variable type suspected
Astrometry
Proper motion (μ) RA: -21.32 mas/yr
Dec.: -10.10 mas/yr
Distance163 pc
Absolute magnitude (MV)−0.29
Orbit
Primary26 Aur A
Companion26 Aur B
Period (P)52.735±0.156 yr
Semi-major axis (a)0.154±0.001"
(21.1+3.2
−2.4
 AU
)
Eccentricity (e)0.653±0.002
Inclination (i)124.22±0.29°
Longitude of the node (Ω)127.08±0.38°
Periastron epoch (T)1974.927±0.026
Argument of periastron (ω)
(secondary)
309.07±0.14°
Details
26 Aur A
Mass2.1 ± 1.0 M
26 Aur B
Mass3.0 ± 0.4 M
Other designations
26 Aur, BD+30°963, GC 7002, HD 37269, HIP 26536, HR 1914, SAO 58280, PPM 70656, ADS 4229, WDS J05386+3030, GSC 02404-01350
Database references
SIMBADdata

26 Aurigae is a binary star system in the northern constellation of Auriga. It is visible to the naked eye as a faint star with an apparent visual magnitude of 5.41.

The distance to this system remains poorly constrained. The new Hipparcos reduction gives a parallax of 5.76±6.42. The original Hipparcos parallax was given as 7.29±0.96, leading to a distance of 137.2+20.8
−16.0
 pc
being assumed in many texts. A distance of 163 pc has been derived from fitting the spectrum.

26 Aurigae is a visual binary system, and the two stars orbit each other every 52.735 years with an ellipticity of 0.653 and an angular separation 0.154. The system is made of a magnitude 6.29 G-type red giant, and a hotter magnitude 6.21 star that has been classified as an early B-type main-sequence star to an A-type subgiant star. Component A is the cool giant star, the brighter but less massive of the pair. The hotter star is sometimes listed as the primary on the basis of its stronger showing in the blended spectrum.