Constellation
Constellation (astronomy), in astronomy, any of 88 imagined groupings of bright stars that appear on the celestial sphere and that are named after religious or mythological figures, animals, or objects. The term also refers to the delimited areas on the celestial sphere that contain the named groups of stars. The oldest known drawings of constellations are motifs on seals, vases, and gaming boards from the Sumerians, indicating that constellations may have been developed as early as 4000 bc. The constellation Aquarius was named by the Sumerians after their god of heaven An, who pours the waters of immortality upon the earth. The division of the zodiac into 12 equal signs was known around 450 BC by the Babylonians. The northern constellations known today are little different from those known by the Chaldeans and the ancient Egyptians, Greeks, and Romans. Homer and Hesiod mentioned constellations, and the Greek poet Aratus of Soli (circa 315-c. 245 bc) gave a verse description of 44 con