Kappa Herculis

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κ Herculis
Hercules Historical View.png
Historical view of the Hercules constellation showing Marfik (κ Her) as the hero's left "elbow".
Observation data
Epoch J2000      Equinox J2000
Constellation Hercules
κ Her A
Right ascension 16h 08m 04.52481s[1]
Declination 17° 02′ 49.1150″[1]
Apparent magnitude (V) 4.994[2]
κ Her B
Right ascension 16h 08m 04.95406s[3]
Declination 17° 03′ 15.6853″[3]
Apparent magnitude (V) 6.25[4]
Characteristics
Spectral type G7III + K0IV[5]
U−B color index +0.630[citation needed]
B−V color index +0.931[citation needed]
Variable type suspected[6]
Astrometry
κ Her A
Radial velocity (Rv) -10.50[7] km/s
Proper motion (μ) RA: -35.55[1] mas/yr
Dec.: -7.04[1] mas/yr
Parallax (π) 8.87 ± 0.55[1] mas
Distance 370 ± 20 ly
(113 ± 7 pc)
Absolute magnitude (MV) -0.22[citation needed]
κ Her B
Radial velocity (Rv) +32.21[8] km/s
Proper motion (μ) RA: -25.70[3] mas/yr
Dec.: -39.45[3] mas/yr
Parallax (π) 1.55 ± 1.98[3] mas
Distance approx. 2,000 ly
(approx. 600 pc)
Details
κ Her A
Mass 3.4[9] M
Radius ~16[10] R
Luminosity 150[10] L
Temperature 4,990[11] K
Metallicity [Fe/H] −0.26[11] dex
Rotational velocity (v sin i) 10[12] km/s
Age ~4.0×108[10] years
Other designations
Marsic, Marfik, Marfak, κ Her, 7 Her, CCDM J16081+1703, NSV 7471, AAVSO 1603+17
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

Coordinates: Sky map 16h 08m 04.526s, +17° 02′ 49.13″

Kappa Herculis (κ Her, κ Herculis) is a double star in the constellation Hercules. κ Herculis A has the proper name Marsic.[13]

Properties[edit]

Kappa Herculis A 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.[10] The Hipparcos mission estimated its distance at roughly 120 parsecs from Earth, or 390 ± 20 light years away.

There is a faint third component κ Herculis C just over 1 arc-minute away.[14] The star 8 Herculis forms a naked-eye pair with κ Herculis.

κ Herculis is a suspected variable star with a reported magnitude range of 4.70 to 5.02.[6]

Nomenclature[edit]

κ Herculis (Latinised to Kappa Herculis) is the system's Bayer designation.

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",[15] a name (or some derivative of which) it shares with Lambda Ophiuchi. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[16] to catalogue and standardize proper names for stars. The WGSN approved the name Marsic for Kappa Herculis A on February 1, 2017 and it is now so entered in the IAU Catalog of Star Names.[13]

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.[17] 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).,[18][19] together with 36 Capricorni in Twelve States (asterism).[20]

References[edit]

  1. ^ a b c d e van Leeuwen, F (November 2007). "Hipparcos, the New Reduction". Astronomy and Astrophysics. Centre de Données astronomiques de Strasbourg. 474 (2): 653–664. Bibcode:2007A&A...474..653V. arXiv:0708.1752Freely accessible. doi:10.1051/0004-6361:20078357. Retrieved 2010-09-26. 
  2. ^ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27. Bibcode:2000A&A...355L..27H. 
  3. ^ a b c d e van Leeuwen, F (November 2007). "Hipparcos, the New Reduction". Astronomy and Astrophysics. Centre de Données astronomiques de Strasbourg. 474 (2): 653–664. Bibcode:2007A&A...474..653V. arXiv:0708.1752Freely accessible. doi:10.1051/0004-6361:20078357. Retrieved 2010-09-26. 
  4. ^ Argue, A. N. (1963). "UBV photometry of 300 G and K type stars". Monthly Notices of the Royal Astronomical Society. 125 (6): 557. Bibcode:1963MNRAS.125..557A. doi:10.1093/mnras/125.6.557. 
  5. ^ Abt, H. A. (1981). "Visual multiples. VII - MK classifications". Astrophysical Journal Supplement Series. 45: 437. Bibcode:1981ApJS...45..437A. doi:10.1086/190719. 
  6. ^ a b Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S. 
  7. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. 
  8. ^ Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics. 430: 165. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. 
  9. ^ Gondoin, P. (December 1999), "Evolution of X-ray activity and rotation on G-K giants", Astronomy and Astrophysics, 352: 217–227, Bibcode:1999A&A...352..217G 
  10. ^ a b c d Kaler, James B. "MARSIC (Kappa Herculis)". University of Illinois. Retrieved 2010-09-26. 
  11. ^ a b McWilliam, Andrew (December 1990). "High-resolution spectroscopic survey of 671 GK giants". Astrophysical Journal Supplement Series. 74: 1075–1128. Bibcode:1990ApJS...74.1075M. ISSN 0067-0049. doi:10.1086/191527. 
  12. ^ "Bright Star Catalogue (Hoffleit+, 1991)". VizieR (5th Revised ed.). Centre de Données astronomiques de Strasbourg. Retrieved 2010-09-26. 
  13. ^ a b "IAU-CSN". 
  14. ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. 
  15. ^ Kurt Vonnegut. "Constellations: Hercules 'the Strongman'". The BBC (British Broadcasting Corporation). Retrieved 2010-11-14. 
  16. ^ "International Astronomical Union | IAU". www.iau.org. Retrieved 2017-04-01. 
  17. ^ (in 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.
  18. ^ (in Chinese) 香港太空館 - 研究資源 - 亮星中英對照表 Archived 2011-01-30 at the Wayback Machine., Hong Kong Space Museum. Accessed on line November 23, 2010.
  19. ^ (in Chinese) English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name Archived 2008-09-24 at the Wayback Machine., Hong Kong Space Museum. Accessed on line November 23, 2010.
  20. ^ Star Names - R.H.Allen p.142

External links[edit]