Globular ClustersGlobular clusters appear to be part of a galaxy's standard make-up. There are over a hundred (probably closer to 200) globular clusters orbiting the Milky Way. Globular clusters have been identified orbiting distant galaxies as well, adding proof that their creation is part of the life cycle of a galaxy.
Globular clusters are vast collections of stars orbiting a common center of gravity. Tens to hundreds of thousands of stars make up their swarm. They orbit their parent galaxies in a more-or-less spherical halo. Their component stars are also very old; this is quite likely a consequence of their presence outside the galay's disk, giving them little chance to create new stars from the gas and dust in the galaxy's richer regions.
Globular clusters can be viewed at any focal length and at any aperture, but like most deep sky objects show off their best at dark sites and with lots of aperture. From my perspective, they show off best starting at 8".
While globular clusters image well at any focal length, they show off their structure at longer focal lengths. This is why I have relatively few images of globular clusters to date.