Description: A globular cluster is a massive, spherically-shaped and densely-packed group of stars that is gravitationally bound and stable over billions of years. In the Milky Way, globular clusters are made up of only very old stars (in general, ages of 11–13 billion years). Globular clusters are some of the oldest objects in the Milky Way. For most globular clusters the constituent stars all formed at approximately the same time although a few globular clusters show evidence of multiple generations of stars. The Milky Way has approximately 160 globular clusters (mostly residing in its halo), while giant elliptical galaxies can have many thousands.

Related Terms:

• Milky Way
• Star Cluster
• Open Cluster

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

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