5 Aurigae

5 Aurigae
Observation data
Epoch J2000      Equinox J2000
Constellation Auriga
Right ascension 05h 00m 18.33887s
Declination +39° 23 40.9241
Apparent magnitude (V) 5.95 (6.02 + 9.50)
Characteristics
Spectral type F5 V
U−B color index −0.03
B−V color index +0.42
Astrometry
Radial velocity (Rv)+6.0±1.3 km/s
Proper motion (μ) RA: 10.87 mas/yr
Dec.: 1.08 mas/yr
Parallax (π)16.74±0.71 mas
Distance195 ± 8 ly
(60 ± 3 pc)
Absolute magnitude (MV)2.07
Orbit
Period (P)1,598.04±50.35 yr
Semi-major axis (a)5.379±0.388
Eccentricity (e)0.536±0.031
Inclination (i)56.1±0.8°
Longitude of the node (Ω)155.4±0.7°
Periastron epoch (T)3,242.73±8.96
Argument of periastron (ω)
(secondary)
333.4±4.5°
Details
5 Aur A
Mass1.48 or 1.70 M
Luminosity12.46 L
Surface gravity (log g)4.14 cgs
Temperature6,603±225 K
Metallicity [Fe/H]−0.02±0.07 dex
Age2.205 Gyr
5 Aur B
Mass0.82 M
Other designations
BD+39° 1133, GC 6084, HD 31761, HIP 23261, HR 1599, SAO 57559, PPM 69817, ADS 3589, CCDM J05003+3924, WDS J05003+3924, TYC 2899-369-1
Database references
SIMBADdata

5 Aurigae is a triple star system in the northern constellation of Auriga, located about 195 light years away from the Sun based on parallax. It is just visible to the naked eye as a dim, yellow-white hued star with an apparent visual magnitude of 5.95. The system is moving away from the Earth with a heliocentric radial velocity of +6 km/s, having come within 62.4 light-years some 8.7 million years ago.

This was initially discovered to be a binary star system by Otto Struve. The outer pair has an orbital period of 1,598 years with an eccentricity of 0.536. The magnitude 6.02 primary, component A, is itself a binary system consisting of two stars of similar mass, roughly 1.5 times the mass of the Sun each, with an orbital period of 8.08 years. It has a stellar classification of F5 V, matching an F-type main-sequence star.

As of 2017, component B is a magnitude 9.50 star at an angular separation of 4.10 from the primary along a position angle of 285°.