Castor and Pollux Castor and Pollux Castor and Pollux (or in Greek, Polydeuces) were twin half-brothers in Greek and Roman mythology, known together as the Dioscuri. Their mother was Leda, but they had different fathers; Castor was the mortal son of Tyndareus, the king of Sparta, while Pollux was the divine son of Zeus, who seduced Leda in the guise of a swan. Though accounts of their birth are varied, they are sometimes said to have been born from an egg, along with their twin sisters Helen of Troy and Clytemnestra. In Latin the twins are also known as the Gemini (literally "twins")
Castor (star) in their spectra, and all are flare stars. "α Geminorum" (Latinised to "Alpha Geminorum") is the star system's Bayer designation. Castor and Pollux are the two "heavenly twin" stars that give the constellation Gemini (meaning "twins" in Latin) its name. The name "Castor" refers specifically to Castor, one of the twin sons of Zeus and Leda in Greek and Roman mythology. The star was annotated by the Arabic description "Al-Ras al-Taum al-Muqadim", which translates as "the head of the foremost twin." In the catalogue of stars in the "Calendarium of Al Achsasi Al Mouakket", this star was designated "Aoul al