Why do globular clusters exist?

Question

What causes old stars to bunch up like globular clusters? It cannot just be gravity alone, can it?

In: 1

Answer 1

The stars in globular clusters are not old. In fact the average age seams to be lower in globular clusters then elsewhere in the galaxy. It seams like globular clusters are formed when dust and gas gets attracted to each other by gravity and then forms into dense clouds. Parts of these clouds are dense enough that gravity takes over completely and it forms into stars. So the stars do not bunch up into a globular cluster but instead they are formed in the cluster.