Constellations are not discovered, but rather are patterns of stars that people have noticed and given names to over time. The earliest evidence for the categorization of stars into constellations comes from Mesopotamia in approximately 1300 to 1000 B.C.
Many of the constellation names still in use as of 2014 have their roots in Greek astronomy, which was based on the constellations of the Mesopotamians; some even use translations of the names applied by the Mesopotamians. The Babylonians also kept records of constellations. Because the Greeks could not see stars in the Southern Hemisphere, some of these constellations were not named until the 16th century.