ASTRONOMY
What’s the difference between a globular cluster and an open cluster?
When it comes to star clusters, size and age matter. Globular clusters are much more massive, and they are usually much older. Open clusters have comparatively fewer stars and are comparatively young – in astronomical terms, that is… And no, there is pretty much nothing in between these two extremes, and the reason for this is as interesting as the question itself.
Globular clusters are relics of an ancient time when the universe had more gas to fuel intense star formation. These conditions no longer exist, or are very rare, in the present universe. Forming a new globular cluster would be a feat, and thus new star clusters are comparatively smaller. There are no old open clusters simply because they have not survived billions of years of interactions with their host galaxies and environment. Instead they have been split apart by gravitational
