Messier 2 or M2 (aka NGC 7089) is a globular cluster in the constellation Aquarius. It’s one of the larger globular clusters known—rich, compact, and significantly elliptical—containing over 150,000 stars. It’s one of the oldest globulars in our galaxy, around 13 billion years old. This Hubble image shows the core of the cluster.
Image Credits: NASA, ESA, STScI, and A. Sarajedini (University of Florida)