Kappa Herculis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| κ Her A | |
| Right ascension | 16h 08m 04.52481s |
| Declination | +17° 02′ 49.1150″ |
| Apparent magnitude (V) | 4.994 |
| κ Her B | |
| Right ascension | 16h 08m 04.95406s |
| Declination | 17° 03′ 15.6853″ |
| Apparent magnitude (V) | 6.25 |
| Characteristics | |
| Spectral type | G7III + K0IV |
| U−B color index | +0.630 |
| B−V color index | +0.931 |
| Variable type | suspected |
| Astrometry | |
| κ Her A | |
| Radial velocity (Rv) | −10.50 km/s |
| Proper motion (μ) | RA: −34.062 mas/yr Dec.: −6.585 mas/yr |
| Parallax (π) | 8.5601±0.1338 mas |
| Distance | 381 ± 6 ly (117 ± 2 pc) |
| Absolute magnitude (MV) | -45 |
| κ Her B | |
| Radial velocity (Rv) | +32.21 km/s |
| Proper motion (μ) | RA: −19.465 mas/yr Dec.: −25.142 mas/yr |
| Parallax (π) | 8.1307 ± 0.0502 mas |
| Distance | 401 ± 2 ly (123.0 ± 0.8 pc) |
| Details | |
| κ Her A | |
| Mass | 3.17 M☉ |
| Radius | 16 R☉ |
| Luminosity | 148 L☉ |
| Surface gravity (log g) | 2.90 cgs |
| Temperature | 5,119 K |
| Metallicity [Fe/H] | +0.04 dex |
| Rotational velocity (v sin i) | 9.9 km/s |
| Age | 309 Myr |
| κ Her B | |
| Radius | 11 R☉ |
| Luminosity | 55 L☉ |
| Temperature | 4,750 K |
| Metallicity [Fe/H] | +0.131 dex |
| Rotational velocity (v sin i) | 1.0 km/s |
| Other designations | |
| Marsic, κ Her, 7 Herculis, CCDM J16081+1703, NSV 7471, AAVSO 1603+17, WDS 16081+1703 | |
| A: HR 6008, HD 145001, HIP 79043, BD+77°2964 | |
| B: HR 6009, HD 145000, HIP 79045, BD+77°2965 | |
| Database references | |
| SIMBAD | κ Her |
| κ Her A | |
| κ Her B | |
Kappa Herculis (κ Herculis, abbreviated Kappa Her, κ Her) is an optical double star in the constellation of Hercules. The two components, Kappa Herculis A (Marsic /ˈmɑːrsɪk/, the traditional name of the system) and B, were 27.3 arc seconds apart in 2000. Based on parallax measurements from the Hipparcos mission, κ Her A is about 113 parsecs (370 light-years) from the Sun and κ Her B is 600 parsecs (2,000 light-years); more recent parallax measurements suggest that B is around 5% more distant than A.
A faint third component Kappa Herculis C is just over 1 arc-minute away. It is at the same distance as κ Her A and has an almost-identical space motion.
The star 8 Herculis forms a naked eye pair with Kappa Herculis 14′ away.