The Hubble Space Telescope captures the Messier 2 star cluster./Courtesy of European Space Agency (ESA), Hubble Space Telescope, National Aeronautics and Space Administration (NASA)

Messier 2 (M2) is a globular cluster mentioned in the list of clusters and nebulas left by the 18th-century French astronomer Charles Messier. M2 is a globular cluster located in Aquarius and is estimated to be about 13 billion years old. It belongs to a large group of globular clusters that orbit around the Milky Way. When Messier discovered M2, he described it as a nebula made of interstellar material and hydrogen, but images taken by the Hubble Space Telescope confirmed that it is a cluster with about 150,000 stars.