duminică, 6 noiembrie 2011

Alpha Phoenicis (α Phe, α Phoenicis) is the brightest star in the constellation Phoenix. It has the traditional name Ankaa, from the Arabic العنقاء al-‘anqā’ "the phoenix". Medieval Arab astronomers formed the constellation of the dhow (small boat) where Phoenix is, so another popular name for the star is Nair al-Zaurak from النائر الزورق an-na’ir az-zawraq "the bright (star) of the skiff".

Ankaa is similar to many of the visible stars of the night sky, being an orange giant of relatively average stellar size. It is currently thought to be in the midst of a short but stable helium burning phase of its stellar evolution, although it probably won't be long in astronomical terms before it sheds its outer layers in a planetary nebula and ends its life quietly as a white dwarf. Ankaa has a small stellar companion, about which little is known.