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Astr110 Photography Projects, Spring 2010

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M3 Globular Cluster in Canes Venatici , Kelsey Clement

M3 Globular Cluster

Messier 3 is a brilliant globular cluster found in the Canes Venatici constellation.  A globular cluster is a large collection of stars that is spherical in shape because gravity pulls all of the stars in close. This globular cluster is quite brilliant because it has an estimated half million stars within it. They are also white because they contain only stars.Charles Messier was the original discoverer of M3 and recorded his finding on May 3, 1764.

The magnitude of M3 is 6.2, which is about 300,000 times the brightness of our sun. The brightest stars in the globular cluster are found to be about 14.2 in magnitude, which is amazingly bright! Also, it is found to be about 40,000 light years away and about 10 billion years old. When measured straight across the densest part of the globular cluster, the angular size is about 3 arc minutes and the linear size is 30 light years. However, when measured from where the stars in the cluster are farther apart, people have found the measurement to be 220 light years across.


"Messier 3." Messier Object Index. <http://www.seds.org/messier/data3.html>.

Plotner, Tammy. "Messier 3" Universe Today <http://www.universetoday.com/guide-to-space/messier-objects/messier-3/>.

Right Ascension (J2000) 13:42:42
Declination (J2000) +28:19:36
Filters used blue(B), green(V), red(R), and clear(C)
Exposure time per filter 30 seconds in C, 30 seconds in BVR
Date observed

March 3, 2010 (C)
March 3, 2010 (BVR)