M54

Credits: ESA / Hubble & NASA

Messier 54 (M54) is an extragalactic globular cluster located in the southern constellation Sagittarius.
M54 has an apparent magnitude of 8.37 and lies at a distance of 87,400 light years from Earth. It has the designation NGC 6715 in the New General Catalogue.
M54 is considered to be the first extragalactic cluster ever discovered.

Facts about M54 by Keith Turnecliff

While M54 is easy to locate, even large amateur telescopes cannot resolve it into individual stars, and binoculars and small telescopes reveal only a round, hazy patch of light. The best time of year to observe the cluster is during the months of June, July and August, but it never rises high above horizon for northern observers.