Sentera was a star system, located somewhere in the space of the galaxy's Alpha or Beta Quadrants.
History and specifics[]
The Sentera system's orbit was the location of a number of worlds, including fifth planet Sentera V, where researchers from the United Federation of Planets discovered a lifeform that existed on sponge-rock colonies, at some point prior to the year 2269. (TOS novel: Vulcan!)