Gamma Corvi (γ Corvi, abbreviated Gamma Crv, γ Crv) is a
binary star and the brightest star in the southern
Corvus, having an
apparent visual magnitude of 2.59. The system's two components are designated Gamma Corvi A (officially named Gienah/ˈdʒiːnə/, traditionally the name of the system)) and Gamma Corvi B, whose magnitude is 9.7 and which is 1.1 arcseconds away from Gamma Corvi A
. The distance to this system has been measured directly using the
parallax technique, yielding an estimated 154
parsecs) from the
Gamma Corvi bore the traditional name of Gienah derived from
Ulugh Beg's الجناح الغراب اليمن al-janāħ al-ghirāb al-yaman, meaning "the right wing of the crow", although on modern charts it marks the left wing. The star
Epsilon Cygni also bore this traditional name and Gamma Corvi was referred to as Gienah Corvi or Gienah Ghurab to distinguish it from this star in Cygnus.
In 2016, the
International Astronomical Union organized a
Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire
multiple systems. It approved the name Gienah for the component Gamma Corvi A on 6 November 2016 and Aljanah for Epsilon Cygni Aa on 30 June 2017. They are both now so included in the List of IAU-approved Star Names.
Al-janāħ al-ghirāb al-yaman or Djenah al Ghyrab al Eymen appeared in the catalog of stars in the Calendarium of Al Achsasi Al Mouakket, which was translated into
Latin as Dextra ala Corvi.
It has a confirmed stellar companion with a mass of about 0.8 times the Sun's, which may be orbiting at a separation of around 50
AU over a 158-year
period. The photometry for Gamma Corvi B suggests a stellar classification in the range K5–M5 V.
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abHouk, Nancy (1978), "Michigan catalogue of two-dimensional spectral types for the HD stars", Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, Ann Arbor: Dept. of Astronomy, University of Michigan, 4,
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