The Crellis Cluster was a stellar cluster located in or near Federation space, near Alpha and Beta Proxima.

In 2266, Commodore Matthew Decker and the crew of the USS Constellation were ordered to host a diplomatic conference in the Cluster following the completion of a survey of the Beta Proxima neutron star. Following a brief diversion to Alpha Proxima II, the Constellation headed for the conference. (TOS - The Brave and the Bold, Book One novella: The First Artifact)