Cardassian Union, Klingon Empire, Romulan Star Empire, United Federation of Planets
The Beta Quadrant is the common designation for one-quarter of the Milky Way Galaxy when viewed from a point of view perpendicular to the plane of the galaxy. It extended ninety degrees spinward of an imaginary line drawn from the centre of the galaxy, the galactic core, passing at least near the Sol system.
Major portions of the Klingon Empire and the Romulan Star Empire are located in the Beta Quadrant. The Federation also claimed territory in the quadrant in the 23rd and 24th centuries.
In 2293, the starship USS Excelsior, commanded by Captain Sulu, completed a three-year exploratory voyage in the Beta Quadrant which included cataloguing gaseous anomalies.
The vast majority of the Gavarian Corridor is in the Beta Quadrant and subsequently, the Nogura primarily operates in this quadrant.