NGC 6809, also known as M55, is a globular cluster located in the constellation Sagittarius. It is approximately 17,600 light-years away from Earth and contains hundreds of thousands of stars. This cluster is notable for its relatively low concentration of stars in its core compared to other globular clusters. Discovered by Jean Philippe Loys de Chéseaux in 1746, NGC 6809 is one of the brighter globular clusters visible from the Southern Hemisphere. It has an apparent magnitude of about 6.3, making it a popular target for amateur astronomers using telescopes.