those are different. A globular cluster contains as many as 100,000 stars and often galaxies contain as much as, or more than, 100,000,000,000 stars. Some of the Messier objects are galaxies, some are nebulae, and others are clusters.


For example M1 and M8 are nebulae, where 2-7 are all clusters. Open clusters are much smaller than globular clusters and more spread out. The first galaxy is M31 or Andromeda.

Hope this helps.

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