Alpha Phoenicis

Alpha Phoenicis (α Phe, α Phoenicis), or Ankaa, is the brightest star in the constellation Phoenix.

Name

Alpha Phoenicis has been given the name Ankaa sometime after 1800, from the Arabic العنقاء al-ʿanqā’ "the phoenix" for the name of the constellation. Medieval Arab astronomers formed the constellation of the dhow (where Phoenix is), so another popular name for the star is Nair al Zaurak from النائر الزوق an-na’ir az-zawraq "the bright (star) of the skiff". The Latin translation is Cymbae, from lūcida cumbæ.

Description

This is a spectroscopic binary star system with components that orbit each other every 3848.8 days (10.5 years). The combined stellar classification of the system is K0.5 IIIb, which matches the spectrum of a lower luminosity giant star. It has an apparent visual magnitude of 2.4, so it is somewhat outshone by its first magnitude neighbors Achernar (α Eridani) and Fomalhaut (α Piscis Australis). Based upon parallax measurements, this system is at a distance of about 85 light-years (26 parsecs) from the Earth. The interferometry-measured angular diameter of the primary component, after correcting for limb darkening, is 5.25 ± 0.06 mas, which, at its estimated distance, equates to a physical radius of about 15 times the radius of the Sun.