Messier 13 (M13), sometimes called the Great Globular Cluster in Hercules, is a globular cluster 25,100 light-years away from Earth, in the constellation of Hercules.
This 11.65 billion year old formation of stars is one of the most observed globular clusters in the northern hemisphere due to it's size and brightness. Containing over 300,000 stars with a diameter of 145 light years. The center of this object is 500 times more concentrated than its outer perimeters. But in general, distance between the stars in a cluster like this is an average of one light-year.
Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. The name of this category of star cluster is derived from the Latin globulus—a small sphere.
M13 was originally discovered by Edmond Halley in 1714. In his notes, he wrote of the cluster: “This is but a little Patch, but it shows it self to the naked Eye, when the Sky is serene and the Moon absent.”
On June 1st, 1764, Charles Messier officially catalogued the star cluster as item 13.
In 1974, a interstellar radio message known as the “Aricebo Message” was sent from Aricebo Observatory carrying basic information about humanity and Earth in the hope that extraterrestrial intelligence might receive and decode it.
INSTRUMENT GPU triplet apo 160/1280 F/8
CAMERA Canon EOS 60Da
MOUNT Fornax 51
GUIDING Lacerta MGen Autoguider
EXPOSURE TIME 33x7min iso 800
LOCATION Gyöngyös, Hungary
