8 Herculis

8 Herculis or 8 Her is an A-type main-sequence star 399 light-years (122.4 parsecs) away in the constellation Hercules. It is also known as HD 145122. Because of its apparent magnitude, of 6.13 the star can be very faintly seen with the naked eye in excellent conditions.

8 Herculis

Location of 8 Herculis (circled in red)
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Hercules[1]
Right ascension	16h 08m 46.6312s[2]
Declination	+17° 12′ 20.292″[2]
Apparent magnitude (V)	+6.13[1]
Characteristics
Evolutionary stage	main sequence[3]
Spectral type	A0Vnn[3]
B−V color index	−0.003±0.005[1]
Astrometry
Radial velocity (Rv)	−17.0±4.3[1] km/s
Proper motion (μ)	RA: −18.098(35) mas/yr[2] Dec.: −31.408(43) mas/yr[2]
Parallax (π)	8.1684±0.0430 mas[2]
Distance	399 ± 2 ly (122.4 ± 0.6 pc)
Absolute magnitude (MV)	+1.18[1]
Details
Mass	2.52[4] M☉
Radius	2.54[4] R☉
Luminosity	55[4] L☉
Surface gravity (log g)	4.03[4] cgs
Temperature	9,863[4] K
Metallicity [Fe/H]	+0.10[5] dex
Rotational velocity (v sin i)	259[3] km/s
Age	317[6] Myr
Other designations
8 Her, BD+17°2967, HD 145122, HIP 79102, SAO 101962[7]
Database references
SIMBAD	data

Stellar properties

8 Herculis is a main-sequence star of spectral type A0Vnn. The nn indicates extremely nebulous spectral lines due to its rapid rotation. The star has about 2.5 times the mass, 2.5 times the radius, and 55 times the luminosity of the Sun. The star appears to have a similar metallicity to the Sun. At 317 million years old, it is modelled to be about 40% of the way through its main sequence life.^[3]