M13 was discovered by Edmond Halley in 1714, and catalogued by Charles Messier on June 1, 1764.
With an apparent magnitude of 5.8, it is barely visible with the naked eye on a very clear night. Its diameter is about 23 arc minutes and it is readily viewable in small telescopes. Nearby is NGC 6207, a 12th magnitude edge-on galaxy that lies 28 arc minutes directly north east. A small galaxy, IC 4617, lies halfway between NGC 6207 and M13, north-northeast of the large globular's center.
M13 is about 145 light-years in diameter, and it is composed of several hundred thousand stars, the brightest of which is the variable starV11 with an apparent magnitude of 11.95. M13 is 25,100 light-years away from Earth.
Every day our eyes catch the light of our memories – time spent with family, the journey to work, a special holiday, a beautiful sunset or a dark starlit night. Each image captured is a picture drawn in light – a photograph: only to be lost in our minds or forever forgotten. Nearly two hundred years ago a small group of amateur scientists achieved what had eluded mankind for centuries – the ability to capture a permanent record of an image seen by their own eyes – a moment in time frozen onto a surface. They had discovered Photography. They were the ‘Catchers of the Light’.