Star clusters are groups of stars which are gravitainally bound together. Two major groups exist.
Globular clusters which are very large dense groups containing thousands of usually rather old stars. Most globular clusters can be found in the central bulge of a galaxy. Some well known examples are M13 in Hercules and Omega Centauri. Our own galaxy contains roughly 150 of such globular clusters.
Open clusters are entirely different. They usually are rather loose and containing only a few dozen stars. Open clusters are usally rather young and often they can even be found in the nebulosity of the clouds in chich they were born. Some ntably clusters are the Pleiades and Hyades in Taurus. Both these clusters cab be seen with the naked eye.
Globular clusters can be almost as old as the universe itself
Open clusters often can be found in the molecular clouds from which they formed
Open clusters are fun to observe visually. They are less harmed by light pollution, can contain many colorful stars and sometimes have fun figures in them. Like a saxofphone can be seen in M35 in Gemini
© Wouter D'hoye 2016 - Last update February 1st 2015