The Great Cluster in Hercules was discovered in 1714 by Edmond Halley. It is one of the most prominent and best known globular clusters in the universe. It is located in the constellation Hercules. Its distance is 25,100 light years; we find that the maximum angular size of 209.6 arc minutes, which corresponds to a linear size of 250 light years. It is too far away to see clearly with the naked eye, but using a telescope reveals the cluster of stars. It was not categorized until 1764, by Charles Messier and is also known as M13. It is located between the two brightest stars seen in during the summer: Vega and Arcturus.
The distance of the Great Cluster in Hercules is 25,100 light years; we find that the maximum angular size of 209.6 arc minutes, which corresponds to a linear size of 250 light years. In my picture you can see that there is an obvious pull to the center of the cluster; this is due to gravity. The gravitational pull shows that there is an obvious semi-uniform semi-circle being formed. . Since I used a clear filter it is hard to tell which stars in the cluster are older.
McClure, Bruce. "M13: Great Cluster in Hercules." earthsky.com. Web. Accessed 12 April 2010. <http://earthsky.org/clusters-nebulae-galaxies/m13-finest-globular-cluster-in-northern-skies>
"Hercules Globular Cluster." Messier 13. Web Accessed 12 April 2010. <http://www.seds.org/messier/m/m013.html>
|Right Ascension (J2000)||16:41:00|
|Filters used||C (Clear)|
|Exposure time per filter||60 sec.|
|Date observed||March 23, 2011|