Gamma Boötis

From Wikipedia, the free encyclopedia
Jump to: navigation, search
γ Boötis
Boötes constellation map.png
γ Boötis (upper center)
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 14h 32m 04.67180s[1]
Declination +38° 18′ 29.7043″[1]
Apparent magnitude (V) +3.03[2]
Spectral type A7 III[3]
U−B color index +0.12[2]
B−V color index +0.19[2]
R−I color index +0.08
Variable type Delta Scuti variable[3]
Radial velocity (Rv) −35.5[4] km/s
Proper motion (μ) RA: −115.71[1] mas/yr
Dec.: +151.16[1] mas/yr
Parallax (π) 37.58 ± 0.14[1] mas
Distance 86.8 ± 0.3 ly
(26.61 ± 0.10 pc)
Luminosity 34[3] L
Temperature 7,800[3] K
Rotational velocity (v sin i) 140[3] km/s
Other designations
Seginus, Haris, Ceginus, Segin, 27 Boötis, BD+38°2565, FK5 535, HD 127762, HIP 71075, HR 5435, SAO 64203.[5]
Database references

Gamma Boötis (γ Boötis, abbreviated Gamma Boo, γ Boo), also named Seginus,[6] is a star in the constellation of Boötes. Approximately 85 light years away from the Sun, it belongs to the spectral class A7III and is a Delta Scuti type variable star with a period of 1.13 hours.[3] Its brightness varies from magnitude +3.02 to +3.07.


γ Boötis (Latinised to Gamma Boötis) is the star's Bayer designation.

It bore the traditional names Seginus (alternatively Segin, Ceginus) of uncertain origin and was listed as Haris in Bečvář. Seginus possibly resulted from Latinization of an Arabic form of the Greek name of the constellation of Boötes - Theguius. Haris comes from the Arabic name of the constellation of Boötes, Al Haris Al Sama meaning "the guard". In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[7] to catalogue and standardize proper names for stars. The WGSN approved the name Seginus for this star on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.[6]

In the catalogue of stars in the Calendarium of Al Achsasi al Mouakket, this star was designated Menkib al Aoua al Aisr (منكب العواء الأيسر - mankibu lʿawwaaʾi lʾaysar), which was translated into Latin as Humerus Sinister Latratoris, meaning 'the left shoulder of barker'.[8]

In Chinese astronomy, Seginus is called 招搖, Pinyin: Zhāoyáo, meaning Twinkling Indicator, because this star is marking itself and stand alone in Twinkling Indicator asterism, Root mansion (see : Chinese constellation).[9] 招搖 (Zhāoyáo), westernized into Chaou Yaou, but the name Chaou Yaou was designated for Beta Boötis (Nekkar) by R.H. Allen and the meaning is "to beckon, excite, or move." [10]

In culture[edit]

USS Seginus (AK-133) was a United States Navy Crater class cargo ship named after the star.


  1. ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752Freely accessible, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", SIMBAD, Bibcode:1986EgUBV........0M. 
  3. ^ a b c d e f Balona, L. A.; Dziembowski, W. A. (October 1999), "Excitation and visibility of high-degree modes in stars", Monthly Notices of the Royal Astronomical Society, 309 (1): 221–232, Bibcode:1999MNRAS.309..221B, doi:10.1046/j.1365-8711.1999.02821.x 
  4. ^ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington D.C., Bibcode:1953GCRV..C......0W. 
  5. ^ "gam Boo -- Variable Star of delta Sct type", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-12-18. 
  6. ^ a b "IAU Catalog of Star Names". Retrieved 28 July 2016. 
  7. ^ "IAU working group on star names (WGSN)". Retrieved 22 May 2016. 
  8. ^ Knobel, E. B. (June 1895). "Al Achsasi Al Mouakket, on a catalogue of stars in the Calendarium of Mohammad Al Achsasi Al Mouakket". Monthly Notices of the Royal Astronomical Society. 55: 429. Bibcode:1895MNRAS..55..429K. doi:10.1093/mnras/55.8.429. 
  9. ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 29 日
  10. ^ Richard Hinckley Allen: Star Names — Their Lore and Meaning: Boötes

External links[edit]