Discovered by Edmond Halley in 1714

M13 is perhaps the most famous globular cluster in the Northern Hemisphere.  It is usually one of the first deep space objects a new amateur will try to center in his telescope, and for good reason, it is truly a spectacular sight even in small telescopes.  The cluster is estimated to contains as many as a million stars.  These stars orbit each other wildly in a ball of approximately 100 light years in diameter.  This globular is composed of some of the oldest stars in the Universe.  They are estimated to be over 12 billion years old.  The cluster is located about 25,000 light years from the earth in the direction of the constellation Hercules.

¹http://www.seds.org/messier/m/m013.html