M2 - AQUARIUS GLOBULAR CLUSTER

Messier 2 is a magnificent globular cluster located in the constellation Aquarius, approximately 37,500 light-years from Earth. It is one of the largest known globular clusters, containing around 150,000 stars packed into a sphere roughly 175 light-years in diameter. The cluster is ancient, with an estimated age of about 13 billion years, making it nearly as old as the universe itself. Its stars are predominantly old, metal-poor Population II stars, which give the cluster an overall yellowish hue. M2 was first discovered by the Italian-French astronomer Jean-Dominique Maraldi in 1746 while observing a comet, and it was independently rediscovered and cataloged by Charles Messier in 1760. Through binoculars, M2 appears as a fuzzy star, but a telescope of at least 4 inches aperture begins to resolve individual stars around its edges. The cluster's core is extremely dense and concentrated, classified as a Class II on the concentration scale. M2 also contains a notable number of variable stars, with over 20 RR Lyrae variables identified, which astronomers use as distance indicators. Despite its impressive size and brightness at magnitude 6.5, M2 is often overlooked in favor of showpiece globulars like M13, but it rewards patient observers with a rich and beautiful stellar swarm.

Contains approximately 150,000 stars within a diameter of 175 light-years, located about 37,500 light-years from Earth.