This famous cluster, M44, is also called Praesepe (Latin for "manger"), or the Beehive cluster. It is also one of the objects easily visible to the naked eye, and thus known since prehistoric times. Some ancient lore is associated with it: Greeks and Romans saw this "nebula" as the manger (Greek: Phatne) associated with two asses who eat from it, Asellus Borealis, the Northern Ass (Gamma Cnc, mag 4.7, distance 155 ly) and Asellus Australis, the Southern Ass (Delta Cnc, mag 3.9, distance 155 ly). Erathosthenes reported that these were the asses on which the gods Dionysos and Silenus rode into the battle against the Titans, who were frightened by the animals' braying so that the gods won. As a reward, the asses were put in sky together with Phatne. Aratos (260 B.C.) mentioned this object as "Little Mist", Hipparchus (130 B.C.) included this object in his star catalog and called it "Little Cloud" or "Cloudy Star." Ptolemy mentions it as one of seven "nebulae" he noted in his Almagest, and describes it as "The Nebulous Mass in the Breast (of Cancer)". According to Burnham, it appeared on Johann Bayer's chart (about 1600 A.D.) as "Nubilum" ("Cloudy" Object).
Galileo has first resolved this "nebulous" object, and reported: "The nebula called Praesepe, which is not one star only, but a mass of more than 40 small stars." It was probably later seen and partly resolved in 1611 by Peiresc, the discoverer of the Orion Nebula (M42), and observed as a cluster by Simon Marius in 1612. Charles Messier added it to his catalog on March 4, 1769.
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