<P> A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite . Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers . The name of this category of star cluster is derived from the Latin globulus--a small sphere . A globular cluster is sometimes known more simply as a globular . </P> <P> Globular clusters are found in the halo of a galaxy and contain considerably more stars and are much older than the less dense open clusters, which are found in the disk of a galaxy . Globular clusters are fairly common; there are about 150 to 158 currently known globular clusters in the Milky Way, with perhaps 10 to 20 more still undiscovered . These globular clusters orbit the Galaxy at radii of 40 kiloparsecs (130,000 light - years) or more . Larger galaxies can have more: Andromeda Galaxy, for instance, may have as many as 500 . Some giant elliptical galaxies (particularly those at the centers of galaxy clusters) such as M87, have as many as 13,000 globular clusters . </P>

This is a cluster of stars has lots of heavy elements
find me the text answering this question