FGC was a prefix used by the Federation in the 24th century as part of a naming system for stars and other astronomical objects. (TNG: "Imaginary Friend" , "Schisms" , DS9: "Emissary") The Star Trek Encyclopedia (4th ed., vol. 1, p. 269) noted that, "FGC probably stands for "Federation General Catalog", a variation of a real astronomical text, the "New General Catalogue (NGC)", by J.L.E. Dreyer, first published in 1888."