The globular cluster M13 in the constellation Hercules
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the Space Telescope Science Institute and NASA

Globular Clusters

If you think that this globular cluster looks like a very round elliptical galaxy, you would be right! Elliptical galaxies and globular clusters have a lot in common. There is no gas or dust in a globular cluster, and the stars are old. In fact, some evidence suggests that globular clusters were the first objects to form.

The big difference is size! Globular clusters contain hundreds of thousands or millions of stars. Elliptical galaxies can contain hundreds of billions of stars! And while elliptical galaxies are sometimes round, globular clusters are never elliptical.

Globular clusters are found both in spiral galaxies and elliptical galaxies. The Milky Way, for example, has over one hundred globular clusters throughout it's halo.

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