It’s hard to imagine a world without Star Trek. But, in June of 1969, that’s exactly what there was.

It was on June 3, 1969, that the final episode of the original Star Trek series aired on NBC. From there, it was thought that the show, which had low Nielsen ratings, would fade away like many other series.

Then came syndication. At a time when reruns were part of our every day, Star Trek’s appreciation surged, creating one of the most devoted fan bases in history. In the 1970s, with interest in the show growing, the Filmation animation studio (who already had Saturday morning hits with The Archie Show and Fat Albert and the Cosby Kids) worked closely with Star Trek creator Gene Roddenberry, to bring Star Trek back to network television, in an animated form.

Filmation producer Lou Scheimer wanted to create an animated series of the show during Star Trek’s prime time run, but it never panned out. With reruns returning the series to the zeitgeist, there was no time better than the 70s.

Star Trek: The Animated Series (known simply as Star Trek in the show’s opening credits) debuted on NBC on September 8, 1973. For fans, much was immediately familiar about the series, including the opening narration, “Space, the final frontier…”

Additionally, most of the cast from the original series returned to voice their animated counterparts: William Shatner as Captain Kirk, Leonard Nimoy as Mr. Spock, DeForest Kelley as Dr. “Bones” McCoy, Nichelle Nichols as communications officer Uhura, George Takei as Mr. Sulu and James Doohan as chief engineer “Scotty.”

There were also aspects of this new Star Trek that was fresh and exciting, as animation provided unlimited opportunities to bring the science fiction realm to life. In their book, Saturday Morning Fever: Growing Up with Cartoon Culture, authors Timothy Burke and Kevin Burke discussed this: “In the live-action Trek, makeup was both expensive and unconvincing, but animated Trek characters could be totally alien without costing anything extra. Two crew members were therefore added to the regular mix, Lieutenants Arex and M’ress. Arex was the more impressively imagined of the two, a wizened three-armed alien with bright red skin. M’ress was a feline alien, complete with long tail and mane.”

With Star Trek: The Animated Series, the Filmation studio was also able to realize worlds, settings, and even plots in animation that would have proven challenging (and costly) in live-action.

Additionally, several episodes of the Saturday morning series served as sequels of sorts to some live-action episodes (including the popular “The Trouble with Tribbles”). Star Trek: The Animated Series became a way to keep this engaging universe going and growing.

As with many passionate fanbases, Star Trek: The Animated Series was, and is, divisive (some debate the show being part of the official Star Trek “canon”).

Despite this, Star Trek: The Animated Series (which ran from 1973-1974) kept interest in the series going in a new way at a time before Star Trek feature films, innumerable TV shows, conventions, and almost every corner of pop culture was touched by the show.

Celebrating its fiftieth anniversary this year, Star Trek: The Animated Series can be seen as a creative and well-crafted way to realize the original show in a new medium, “boldly going” where Saturday morning television had never gone before.