Dick Van Dyke became a regular on the upcoming season of "The Carol Burnett Show." It would also be the *final* season for Ms. Burnett's (now-classic) variety show, which ran a total of 11 years.
Two shows on CBS' fall schedule, "The Tony Randall Show" and "Wonder Woman," previously aired on ABC for their first seasons. This second season for each show would be their first on CBS, but the *last* season for both.
Two six-season veterans on CBS' schedule, "The Bob Newhart Show" and "Maude," would each be beginning their *final* seasons that fall on the network. Both series would enter syndication as reruns in the fall of 1978.
Although the UCLA Film and Television Archive currently owns a (non-accessible to the public) videotape of "CBS Galaxy" in their collection (perhaps donated to UCLA by the network), no publicly accessible format of this special is available as of this posting. However, a surviving 30-second promo for "CBS Galaxy" can be seen on You Tube.
The "galaxy" in this special's title seems to have been inspired by the runaway success of the very first "Star Wars" film ("Episode IV: A New Hope"), which was still playing in theaters when "CBS Galaxy" aired.