M13 – The Great Star Cluster in Hercules
M13 was discovered by Edmond Halley in 1714, and cataloged by Charles Messier on June 1, 1764 into his list of objects not to mistake for comets; Messier’s list, including Messier 13, eventually became known as the Messier Catalog. About one third of the way from Vega to Arcturus, four bright stars in Herculēs form the Keystone asterism, the broad torso of the hero. In this M13 can be seen 2⁄3 of the way, north (by west) from Zeta to Eta Herculis. Although only telescopes with great […]
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