Captured using the Stamford observatory's 22-inch telescope in photographic mode.

Discovered by Edmond Halley in 1714.

M13, also called the `Great globular cluster in Hercules', is one of the most prominent and best known globulars of the Northern celestial hemisphere. It was discovered by Edmond Halley in 1714, who noted that `it shows itself to the naked eye when the sky is serene and the Moon absent.' According to Charles Messier, who cataloged it on June 1, 1764, it is also reported in John Bevis' "English" Celestial Atlas.

Globular cluster M13 was selected in 1974 as target for one of the first radio messages addressed to possible extra-terrestrial intelligent races, and sent by the big radio telescope of the Arecibo Observatory.

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Right Ascension	16 : 41.7 (h:m)
Declination	+36 : 28 (deg:m)
Distance	25.1 (kly)
Visual Brightness	5.8 (mag)
Apparent Dimension	20.0 (arc min)