Messier 3 (also known as M3 or NGC 5272) is a globular cluster in the constellation Canes Venatici. It was discovered by Charles Messier in 1764, and resolved into stars by William Herschel around 1784. This cluster is one of the largest and brightest, and is made up of around 500,000 stars. M3 is visible to the naked eye under very good conditions, and it has a visible brightness of 6.2 magnitude. The easiest way to discover this cluster is to look about halfway between the pair of Arcturus and Cor Caroli, just east of Beta Comae (Seds).
The blue dots in the cluster are the hotter stars in the cluster, because blue means heat. The blue stars are also a representation of the newer population of stars in the cluster. (Universe Today).The distance to this object is estimated to be 33,900 light years (Seds); we find a maximum angular size of 110 acrseconds or 1.8 arcminutes, which corresponds to a linear size of 308 light years.
|Right Ascension (J2000)||13:42:12|
|Filters used||B (Blue), C (Clear), R (Red), V (Green)|
|Exposure time per filter||B, V, R, and C (300s)|
|Date observed||March 23, 2011 4:30:12 ET|