Omega Herculis

Omega Herculis

Historical view of the Hercules constellation showing the star Kajam (ω Her) as "the club" in the hero's right hand.
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Hercules
Right ascension 16h 25m 24.95425s
Declination +14° 01 59.7711
Apparent magnitude (V) 4.5821 (4.58 + 11.5)
Characteristics
Spectral type A2 Vp CrSr
U−B color index +0.01
B−V color index +0.00
Variable type α2 CVn
Astrometry
Radial velocity (Rv)−5.90±0.74 km/s
Proper motion (μ) RA: +40.86 mas/yr
Dec.: −59.71 mas/yr
Parallax (π)13.04±0.64 mas
Distance250 ± 10 ly
(77 ± 4 pc)
Absolute magnitude (MV)0.29±0.15
Details
ω Her A
Mass2.14 M
Radius3.30 R
Luminosity70 L
Surface gravity (log g)3.51±0.35 cgs
Temperature10,052±320 K
Metallicity [Fe/H]+0.47±0.15 dex
Rotation2.951 d
Rotational velocity (v sin i)55 km/s
Age149 Myr
Other designations
Cujam, ω Her, 24 Her, 51 Ser, BD+14°3049, FK5 613, HD 148112, HIP 80463, HR 6117, SAO 102153, WDS J16254+1402AB
Database references
SIMBADdata

Omega Herculis (ω Herculis, abbreviated Ome Her, ω Her) is a binary star system in the northern constellation of Hercules. Based upon an annual parallax shift of 13.04 mas as seen from Earth, it is located around 250 light-years from the Sun. It is faintly visible to the naked eye, having a combined apparent visual magnitude of 4.58. The system is a candidate for membership in the Ursa Major Moving Group, although this remains uncertain.

The two components are designated Omega Herculis A (officially named Cujam /ˈkjuːəm/, the traditional name of the system) and B.