| component2 = B
| mass2 = 2.0[3]
| radius2 = 2.6[3]
| luminosity2 = 26.3[3]
| temperature2 = 8.150[3]
| age_myr2 =740[3]
}}{{Starbox catalog
| names = Kitalphar, 8 Equulei, HR 8131, HD 202447, BD +04 4635, HIP 104987, SAO 126662, FK5 800, GC 29735
}}{{Starbox reference
| Simbad = Alpha+Equulei
}}{{Starbox end}}Alpha Equulei (α Equulei, abbreviated Alpha Equ, α Equ), also named Kitalpha,[4] is a star in the constellation of Equuleus. It is a high proper motion star only 190 light years away.
Nomenclature
α Equulei (Latinised to Alpha Equulei) is the star's Bayer designation.
It bore the traditional name Kitalpha (rarely Kitel Phard or Kitalphar), a contraction of the Arabic name قطعة الفرس qiṭ‘a(t) al-faras "a piece of the horse". In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[5] to catalogue and standardize proper names for stars. The WGSN approved the name Kitalpha for this star on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.[4]
In Chinese, {{lang|zh|虚宿}} ({{lang|zh-Latn|Xū Sù}}), meaning Emptiness, is an asterism consisting of Alpha Equulei and Beta Aquarii.[6] Consequently, Alpha Equulei itself is known as {{lang|zh|虛宿二}} ({{lang|zh-Latn|Xū Sù èr}}, {{lang-en|the Second Star of Emptiness}}.)[7]
Properties
The overall appearance of α Equulei is a G-type giant[8] with an apparent magnitude of +3.92, but it is a spectroscopic binary consisting of two individual stars.
The primary star is a G7 giant about fifty times more luminous than the sun. It has an effective temperature of 5,100 K and a radius of 9.2 times greater than the sun.
The secondary is an A-type dwarf about 26 times as luminous as the sun. It has an effective temperature of 8,150 K and a radius 2.6 times greater than the sun. It is a chemically peculiar Am star.[3]
The two stars revolve in a circular orbit every 98.8 days. Their respective orbital velocities allow their masses to be calculated at {{solar mass|2.3}} and {{solar mass|2.0}} respectively.[3]
References
1. ^1 2 {{cite journal|bibcode=1984SAAOC...8...59C|title=Standardization of Broadband Photometry of Equatorial Standards|journal=South African Astronomical Observatory Circulars|volume=8|pages=59|author1=Cousins|first1=A. W. J.|year=1984}}
2. ^1 2 3 4 {{cite journal | title=Validation of the new Hipparcos reduction | url=http://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html | last1=van Leeuwen | first1=F. | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | year=2007 | arxiv=0708.1752 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 }}Vizier catalog entry
3. ^1 2 3 4 5 6 7 8 9 10 11 12 13 14 {{cite journal|bibcode=2002MNRAS.330..288G|title=Composite spectra Paper 11: α Equulei, an astrometric binary with an Am secondary|journal=Monthly Notices of the Royal Astronomical Society|volume=330|issue=2|pages=288|author1=Griffin|first1=R. E. M.|last2=Griffin|first2=R. F.|year=2002|doi=10.1046/j.1365-8711.2002.05030.x}}
4. ^1 {{cite web | url=http://www.pas.rochester.edu/~emamajek/WGSN/IAU-CSN.txt | title=IAU Catalog of Star Names |accessdate=28 July 2016}}
5. ^{{citation | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | title=IAU Working Group on Star Names (WGSN) | publisher=International Astronomical Union | accessdate=22 May 2016 | postscript=. }}
6. ^{{zh icon}} 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}}.
7. ^{{zh icon}} 香港太空館 - 研究資源 - 亮星中英對照表 {{webarchive|url=https://web.archive.org/web/20110129031951/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_h_l.htm |date=2011-01-29 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.
8. ^{{cite journal|bibcode=1999A&AS..134..473G|title=Spectral classifications in the near infrared of stars with composite spectra. III. Study of a sample of 137 objects with the Aurelie spectrograph|journal=Astronomy and Astrophysics Supplement|volume=134|issue=3|pages=473|author1=Ginestet|first1=N.|last2=Carquillat|first2=J. M.|last3=Jaschek|first3=C.|year=1999|doi=10.1051/aas:1999444}}