Globular Clusters

In our galaxy we can find many globular clusters. There are around 158 known globular clusters in our galaxy. These clusters are most often found in the galactic halo, but they do orbit the center of the Milky Way.

A globular cluster contains around 1 million stars and they are about 15 parsecs in diameter.  This means that the stars in the clusters are very close together.

Globular clusters actually help astronomers look back in time because they are all around 12 billion years old. Since they are 12 billion years old the stars in the globular clusters are all very old, red, and have low masses.  This is why globular cluster sometimes appear red in images.  

Globular clusters are very tightly bound by gravity.  If you look at images of globular clusters you can observe that their centers are very bright and stars have more distance between them the farther they are located from the center.