spherical cluster

astronomy

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July 14, 2026

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A globular cluster is a dense, spherical collection of old stars, numbering from thousands to hundreds of thousands. These ancient stellar systems are among the oldest objects in the Milky Way Galaxy, with ages estimated between 11 and 13 billion years. They are typically found in the galactic halo, a spherical region surrounding the galactic disk.12

Globular clusters are extremely luminous, with a mean luminosity equivalent to about 25,000 Suns. Their stars are predominantly composed of hydrogen and helium, with a very low abundance of heavier elements, or metals, compared to stars in the galactic plane. Investigations of globular clusters have been crucial in understanding the structure and history of the Milky Way Galaxy.13

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Spherical clusters
Spherical clusters are dense and consist almost exclusively of elliptical and S0 galaxies. They are enormous, having a linear diameter of up to 50,000,000 light-years. Spherical clusters may contain as many as 10,000 galaxies, which are concentrated toward the cluster centre.
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Spherical clusters are dense and consist almost exclusively of elliptical and S0 galaxies. They are enormous, having a linear diameter of up to 50,000,000 light-years. Spherical clusters may contain as many as 10,000 galaxies, which are concentrated toward the cluster centre.
Read More