Kappa Herculis
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Hercules |
| Right ascension | 16h 08m 04.5255s[1] |
| Declination | 17° 02′ 49.129″[1] |
| Apparent magnitude (V) | 5.1628[2]
|
| Characteristics | |
| Spectral type | G8III [1] |
| U−B color index | +0.630 |
| B−V color index | +0.931 |
| Astrometry | |
| Radial velocity (Rv) | -11.0[1] km/s |
| Proper motion (μ) | RA: -34.29[1] mas/yr Dec.: -5.46[1] mas/yr |
| Parallax (π) | 8.40 ± 1.23[3] mas |
| Distance | approx. 390 ly (approx. 120 pc) |
| Absolute magnitude (MV) | -0.22 |
| Details | |
| Mass | 3.4[4] M☉ |
| Radius | ~16[5] R☉ |
| Luminosity | 150 [5] L☉ |
| Temperature | 4,990 [5][6] K |
| Metallicity | −0.26 Fe/H[6] |
| Rotational velocity (v sin i) | 10[7] km/s |
| Age | ~4.0×108[5] years |
| Other designations | |
| Database references | |
| SIMBAD | data |
Coordinates: 
16h 08m 04.526s, +17° 02′ 49.13″
Kappa Herculis (κ Her, κ Herculis) is a double star in the constellation Hercules. Traditional names that have been attributed to the star are "Marfik", "Marfak" or "Marsic", all of which come from the Arabic لمرفق Al-Mirfaq meaning "the elbow",[8] a name (or some derivative of which) it shares with Lambda Ophiuchi.
Properties
Kappa Herculis is a giant star with stellar classification G8III. With a mass of 3.0 M☉ and radius that is 16 R☉, the star boasts a total bolometric luminosity that is 150 L☉.[5] Its apparent magnitude has been recently recalibrated at 5.1628.[2] The Hipparcos mission estimated its distance at roughly 120 parsecs from Earth, or 390 ± 20 light years away.
Etymology
In Chinese, 天市右垣 (Tiān Shì Yòu Yuán), meaning Right Wall of Heavenly Market Enclosure, refers to an asterism which is represent eleven old states in China which is marking the right borderline of the enclosure, consisting of κ Herculis, β Herculis, γ Herculis, γ Serpentis, β Serpentis, δ Serpentis, α Serpentis, ε Serpentis, δ Ophiuchi, ε Ophiuchi and ζ Ophiuchi.[9] Consequently, κ Herculis itself is known as 天市右垣三 (Tiān Shì Yòu Yuán sān, English: the Third Star of Right Wall of Heavenly Market Enclosure), represent the state Jin (晉) (or Tsin).,[10][11] together with 36 Capricorni in Twelve States (asterism).[12]
See also
- Lists of stars in the constellation Hercules
- Class G Stars
- Giant star
- Double star
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 5.0 5.1 5.2 5.3 5.4 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 6.0 6.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ (Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
- ↑ (Chinese) 香港太空館 - 研究資源 - 亮星中英對照表, Hong Kong Space Museum. Accessed on line November 23, 2010.
- ↑ (Chinese) English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name, Hong Kong Space Museum. Accessed on line November 23, 2010.
- ↑ Star Names - R.H.Allen p.142
External links
- Jim Kaler's Stars, University of Illinois: MARSIC (Kappa Herculis)
- Hercules constellation map showing: κ Herculis
