8 Persei

8 Persei is a single^[8] star in the northern constellation of Perseus,^[7] located 416 light years away from the Sun.^[1] It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.757.^[2] There is an estimated 52% chance that the star may be a member of the Hyades–Pleiades stream of co-moving stars.^[9]

8 Persei

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Perseus
Right ascension	02h 17m 59.88750s[1]
Declination	+57° 53′ 59.3529″[1]
Apparent magnitude (V)	5.757[2]
Characteristics
Spectral type	K3 III[3]
B−V color index	1.203[2]
Astrometry
Radial velocity (Rv)	0.72[2] km/s
Proper motion (μ)	RA: +60.568[1] mas/yr Dec.: +5.812[1] mas/yr
Parallax (π)	7.8492±0.1017 mas[1]
Distance	416 ± 5 ly (127 ± 2 pc)
Absolute magnitude (MV)	0.26[4]
Details
Mass	1.83[2] M☉
Radius	15.85±0.99[5] R☉
Luminosity	107.95±1.69[1] L☉
Surface gravity (log g)	2.3[5] cgs
Temperature	4,560+92 −86[1] K
Metallicity [Fe/H]	−0.07[5] dex
Rotational velocity (v sin i)	1.0[6] km/s
Age	2.36[2] Gyr
Other designations
8 Per, BD+57°535, FK5 2157, HD 13982, HIP 10718, HR 661, SAO 23143[7]
Database references
SIMBAD	data

With an age of over two billion years,^[2] this is an aging red giant of spectral type K3 III,^[3] a star that has used up its core hydrogen and is expanding. It has 1.83^[2] times the mass of the Sun and has reached nearly 16^[5] times the Sun's size. The star is radiating 108^[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,560 K.^[1]