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M5, Globular Cluster
Marie Ross


This is the globular cluster M5. A Globular Cluster is a spherical collection of stars that orbits a galactic core and is tightly bound by gravity. It was first seen in 1702 on May 5 by Gottfried Kirch. He was observing a comet with his wife when he spotted this cluster. It was first described as something that does not have any stars, which was later proved wrong by William Herschel. It is one of the oldest clusters at the age of 13 billion years old. It is one of the largest globular clusters with a diameter of 165 light years. The distance of this cluster is about 24,500 light years and that diameter is at 23 minutes of arc. Then this gives the cluster a linear size of 1,065.21.The tidal radius is torn away by the Milky Way Galaxy's tidal gravitational forces.

This picture above, globular cluster m5, has about 100,00 stars in its cluster The clusters are formed because of a gravitational bound. These thousands of stars orbit the center of the cluster and this very clsuter orbits the center of our Milky Way Galaxy. The very center of this picture is very bright because that is when the stars become very compacted due to gravitational bounds. As you go further out towards the edges of this photo the stars become less and lessbecause they are less compacted as you draw away from the center. The stars in this cluster grow fainter as you go out from the center. The brighter yellow spots that surround the bright center are bright stars. The smaller stars are blue, which indicates that they are colder. The bigger stars are red, which indicates that they are warm stars. These red stars are also brighter and the blue stars are dimmer. When there are more bigand bright stars, this means that the cluster is old and this one is indeed very old.


S.I.Bailey. "Messier 5." The periods of the variable stars. 2007 Aug. 21. Accessed 19 April. 2011. <>

Malin, David. "AAT 70 ." Astonomy Picture of the Day. Web. 19 April. 2011. <>.


Right Ascension (J2000) 15:18:36
Declination (J2000) +02:05:00
Filters used B (Blue), C (Clear), R (Red), V (Green)
Exposure time per filter B,V,C, and R (60s)
Date observed March 24, 2011 UT



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