ALNATH is the alpha or brightest star of the constellation Aries in medieval star maps. The name is also given to the first mansion of the moon. Modern astronomers give the name to the beta or second brightest star of Taurus, in the tip of one horn. It is also the gamma or third brightest star of Auriga, the Charioteer, located in his left ankle, which overlaps with the horn of Taurus.

The magician from Orleans finds the moon's position by calculating the distance between Alnath in the head of Aries in the eighth sphere and the head of the fixed Aries above it in the ninth sphere or primum mobile above it, FranklT 1281-1284. [Aries: Ram: Taur]

The name is the ME variant of Arabic al-nath, the butting one, derived from the verb nataha, to butt with the horns.