Magnitude 3.58 Apparent magnitude (V) 3.58 | Constellation Capricornus | |
Similar Gamma Capricorni, Omega Capricorni, Beta Capricorni, Psi Capricorni, Delta Capricorni | ||
Alpha² Capricorni (α² Capricorni, abbreviated Alpha² Cap, α² Cap), also named Algedi, is a star in the constellation of Capricornus. It is a yellow G-type giant with an apparent magnitude of +3.58 and is approximately 109 light years from the Sun. It forms part of the double star Alpha Capricorni along with α¹ Capricorni.
Nomenclature
α² Capricorni (Latinised to Alpha² Capricorni) is the star's Bayer designation.
It bore the traditional names Secunda Giedi or Algiedi Secunda and shared the name Algedi (from the Arabic الجدي al-jadii 'the goat') with α¹ Capricorni. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Algedi for α² Capricorni on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.
In Chinese, 牛宿 (Niú Su), meaning Ox (asterism), refers to an asterism consisting of α² Capricorni, Beta Capricorni, ξ² Capricorni, Pi Capricorni, Omicron Capricorni and Rho Capricorni. Consequently, α² Capricorni itself is known as 牛宿二 (Niú Su èr, English: the Second Star of Ox.)