(covers information from several alternate timelines)
Procyon was a star system in the Alpha Quadrant. Located less than 20 light years from Sol, this system consisted of binary companion stars, Procyon A and Procyon B. This system had at least five planets.
On several occasions in 2364, viewscreen readouts aboard the USS Enterprise-D showed the location of the A and B Procyon stars, in the form of a star chart from the Enterprise library computer. (TNG: "The Naked Now", "The Last Outpost", "Conspiracy")
This chart naming stars within 20 light years of Sol was drawn by Rick Sternbach for the Star Trek Spaceflight Chronology in the late 1970s. Found on page 77, this chart showed Earth commercial and exploration routes after the use of warp drive began. There were no commercial or exploration routes to this system. The stars Alpha Centauri, Sol, Sirius, and Tau Ceti were identified on "The Explored Galaxy" wall chart as being located in the Alpha Quadrant..
Procyon (Alpha Canis Majoris) was located in or near Federation, in the Andorian Sector (Sector 006). This sector was located in the Beta Quadrant. The homeworld of the Andorians, Andor (Andoria), was located in this system. This was a binary star system. Procyon A was a F class star with a magnitude of +3, which was ten times brighter than Sol. Procyon B was an A class star. (Pgs 19, 45, 60)