Another fine globular
cluster to be found in Sagittarius is M55. This is a large
cluster with a somewhat loose arrangement of stars. Its apparent
size is about 2/3 that of the full moon. It has a diameter of
about 110 light-years, and is believed to be located only 20,000
light-years from Earth. This would make it among the closest of
the globular clusters. M55 has been described as very grainy in
appearance, due to its loose structure. Its size and brightness
make it easy to identify in binoculars. Through a small
telescope, its grainy structure will be more apparent.
