NGC 5466

A cluster of about 50,000 stars, NGC 5466 is the starting point of an enormous stream of stars that orbits around the Milky Way in a process of tidal stripping.

At some point - particularly when its orbit takes it close to the galactic center - the cluster can no longer hang onto its most outlying stars, and these stars drift off into orbits of their own. The lost stars that find themselves between the cluster and the galactic center begin to move slowly ahead of the cluster in its orbit, while the stars that drift outward and away from the galactic center fall slowly behind.