Messier 2

Messier 2 (M2) is a globular cluster in the Aquarius constellation about 37,000 light years away.

Globular clusters are large, roughly spherical, tightly gravitationally bound collections of stars. They tend to live in galactic halos, oribiting almost every type of galaxy. The Milky Way has roughly 200 of them orbiting its main body.

Globular clusters are ancient. They are many billions of years old—usually 10 to 13 billion years old—and are almost as old as the universe itself. The stars they contain tend to be very old as well, because star formation inside the cluster has largely ceased. The formation of globular clusters is not well understood. Current research leans toward the idea that they formed from very dense molecular clouds in the early universe. Some larger globular clusters may once have been dwarf galaxies whose larger star populations were stripped away from the core by larger galaxies.

M2 Facts

Distance: 37,000 light years

Number of stars: 150,000

Diameter: 175 light years

Age: 13 billion years