Station Nigala IV was a space station. In 2366, it was the destination of the USS Enterprise-D following its humanitarian mission to Bre'el IV. (TNG: "Deja Q" ) This space station was only mentioned in dialogue. According to Star Trek: Star Charts ("United Federation of Planets III") and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), Station Nigala IV was located in the Alpha Quadrant.