ARIES (the "Ram"), in astronomy, the first sign of the zodiac, denoted by the sign 'F, in imitation of a ram's head. Accord ing to a Greek myth, Nephele, mother of Phrixus and Helle, gave her son a ram with a golden fleece. To avoid the evil designs of Hera, their stepmother, Phrixus and Helle fled on the back of the ram, and reaching the sea, attempted to cross. Helle fell from the ram and was drowned (hence the Hellespont) ; Phrixus, having arrived in Colchis, sacrificed the ram to Zeus, who placed it in the heavens as the constellation.
The "first point of Aries," which is now far away from the constellation and is situated in Pisces, is the zero from which the right ascensions and longitudes of the stars are measured. It is at the crossing point of the equator and ecliptic on the celestial sphere.