6 Persei

6 Persei is a binary star^[8] system in the northern constellation of Andromeda.^[9] It is faintly visible to the naked eye with an apparent visual magnitude of 5.29.^[3] The system is located 182 light years from Earth, as determined from its annual parallax shift of 17.9 mas.^[2] It is moving further away with a heliocentric radial velocity of +42 km/s.^[5] The system has a relatively high rate of proper motion, traversing the celestial sphere at the rate of 0.386 arcsecond/year.^[10]

6 Persei

Location of 6 Persei (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Andromeda[1]
Right ascension	02h 13m 36.34084s[2]
Declination	+51° 03′ 56.8222″[2]
Apparent magnitude (V)	5.29[3]
Characteristics
Spectral type	G8.5 IIIb Fe-2[3]
B−V color index	0.926[4]
Astrometry
Radial velocity (Rv)	+41.82±0.27[5] km/s
Proper motion (μ)	RA: +344.397[2] mas/yr Dec.: −164.853[2] mas/yr
Parallax (π)	17.8901±0.0943 mas[2]
Distance	182.3 ± 1.0 ly (55.9 ± 0.3 pc)
Absolute magnitude (MV)	+1.25±0.07[6]
Orbit[6]
Period (P)	1,576.23±0.04 d
Eccentricity (e)	0.8828±0.0007
Inclination (i)	104°
Periastron epoch (T)	2,450,307.31±0.12 JD
Argument of periastron (ω) (secondary)	266.4±0.3°
Semi-amplitude (K1) (primary)	19.82±0.06 km/s
Details[4]
Mass	1.5 M☉
Radius	7 R☉
Luminosity	26.3 L☉
Surface gravity (log g)	3.0 cgs
Temperature	4,920 K
Metallicity [Fe/H]	−0.60 dex
Rotational velocity (v sin i)	0.0 km/s
Other designations
NSV 747, AG+50°249, BD+50°481, FK5 77, HD 13530, HIP 10366, HR 645, SAO 23047, PPM 27263, WDS J02136+5104A[7]
Database references
SIMBAD	data

This is a single-lined spectroscopic binary with an orbital period of 4.3155 yr and an eccentricity of 0.88. The a sin i value for the primary is 201.8±0.9 Gm, where a is the semimajor axis and i is the orbital inclination. The inclination is estimated to be 104°.^[6]

The visible component is an evolved giant star with a stellar classification of G8.5 IIIb Fe-2,^[3] where the suffix notation indicates an underabundance of iron in the spectrum. It has 1.5 times the mass of the Sun and has expanded to 7 times the Sun's radius. The star is radiating 26 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,920 K.^[4] It has a magnitude 10.49 visual companion at an angular separation of 108.9″ along a position angle of 57°, as of 2004.^[11]