Messier 56 is a moderately bright globular cluster discovered by Charles Messier in 1779, appearing as a dense, round patch of stars in the rich star fields of the Milky Way. Its core is compact, with many individual stars resolvable in medium to large telescopes, and it is particularly appreciated for its subtle color variations, with hints of blue and yellow stars visible in deep images. While not as frequently photographed as some other Messier globulars, M56 is easily accessible even from light-polluted locations and offers rewarding results for astrophotographers using modest equipment. The cluster is moving through the Milky Way on a retrograde orbit, traveling in the opposite direction to the galaxy’s spiral arms.
Names and Catalog numbers
- Messier 56
- M56
- NGC 6779
- Melotte 220
Position and the cosmic neighborhood
Messier 56 is situated in the constellation Lyra, nearly midway between the bright star Albireo in Cygnus and Sulafat in Lyra, and not far from the famous Ring Nebula (M57). Its location places it within a dense field of Milky Way stars, making wide-field astrophotography especially attractive. The cluster is best found by drawing a line between Albireo and Sulafat and searching slightly closer to Albireo. Several faint background stars and the proximity to M57 allow for interesting compositions in astrophotographic images.
Nice to Know
- M56 is estimated to be about 13 billion years old, making it one of the older globular clusters in the Milky Way.
- The cluster is rarely photographed compared to other Messier globulars, but it is easy to image and rewarding for astrophotographers of all levels.
- M56 travels through the Milky Way on a retrograde orbit, which is unusual among globular clusters.
- Its core is dense, but many individual stars can be resolved with telescopes of 8 inches (20 cm) or larger, revealing subtle color differences.
Brightnes, distance and size
Messier 56 has an apparent magnitude of 8.3, making it accessible in binoculars and small telescopes under dark skies, though best resolved with larger apertures. The cluster lies about 32,900 to 33,000 light-years from Earth, with a diameter ranging from approximately 55 to 85 light-years, depending on the measurement method. Its apparent size is about 7 to 9 arcminutes, which is about a third the apparent diameter of the full Moon, making it a compact but striking target for astrophotography.
