Today marks the 46th anniversary of the first airing of a little television show called Star Trek. On this day in 1966, viewers first glimpsed Kirk, Spock, Bones, the Enterprise and an array of bright, color-coded costumes. And though it’s hard to imagine the landscape of science fiction storytelling without Star Trek, the series easily could have turned into something very different from the phenomenon we all recognize today. Here are five big turning points that could have resulted in five alternate realities of Star Trek history.

5.) “The Cage” is approved; Captain Pike leads a mostly white Enterprise

When we think of classic Star Trek today, we’re quick to praise its groundbreaking racial diversity. Dr. Martin Luther King, Jr. was a fan of the show and famously urged Nichelle Nichols to remain on the program. But the first pilot episode Trek-creator Gene Rodenberry sent to NBC was not the rainbow coalition the Starship Enterprise eventually housed. Instead, “The Cage” featured a mostly white crew, with a much grumpier captain than Jim Kirk: Jeffrey Hunter’s Captain Christopher Pike. Sure, Majel Barrett played the ship’s female first officer, but beyond that the cast looked a lot like the crew in Forbidden Planet: white-bread boys with crew cuts.

Supposedly, the network execs passed on “The Cage” because it was “too cerebral,” and a more fun (and diverse) Star Trek was born. But what if it hadn’t been that way? In terms of story and conceptual science fiction, “The Cage” is awesome, but the aesthetic of this version of the Enterprise just isn’t as welcoming as what it would become. Even “Where No Man Has Gone Before” has similar problems, and it’s not until Uhura and Sulu show up and the crew are in their proper outfits that Star Trek feels right. So, there’s a chance that NBC was right for the wrong reasons. Star Trek may not have caught on with 60’s culture and beyond if it had looked like Jeffery Hunter. But when Star Trek looked like William Shatner and Nichelle Nichols, things got sexy.

4.) The Next Generation never hires Ronald D. Moore

There are a lot of influential writers and producers from the “contemporary” era of Star Trek, but Ronald D. Moore might be the most important. Famously, The Next Generation actually had a unusual open submission policy for scripts. (Seriously, can you imagine if Doctor Who had that now?) In 1989, Moore sold a script called “The Bonding” and within a year was hired as a staff writer. From this point on his influence on Star Trek would be considerable: not only was he a huge presence in the TNG writers room, he co-wrote 27 episodes, including the finale, “All Good Things.” He also wrote Star Trek: Generations AND Star Trek: First Contact, was in charge of the Deep Space Nine writers room from its 3rd season to its 5th season, and briefly wrote for Voyager. What was Moore’s impact on Star Trek? Well, despite being a huge Trek fan, Moore disagreed with the Roddenberry directive involving Starfleet people NOT being allowed to bicker with each other. In short, Moore is a big believer in character conflict driving a story.

To get around the constraints of Starfleet characters not being allowed to have a lot of arguements with each other, Ron Moore found ways of having alien (non-Starfleet) characters in conflict with human ones. A lot of this can been seen on Deep Space Nine, and in terms of preserving Star Trek as a serious drama, this sensibility was absolutely essential. From the TNG episode “Family” to the DS9 episode “Inter Arma Enim Silent Leges,” Moore’s scripts tackled some serious, almost kitchen sink-style theatrical realism.

These days, Ron Moore is probably even better known for being the mastermind behind the Battlestar Galatica relaunch. But if Star Trek had never hired him, it might have lost some of its soul, and the entire landscape of TV science fiction would be vastly different. In short, not only would you have a less cool DS9, you might have never had Battlestar Galactica at all!

3.) Star Trek: Phase II TV show happens, Star Trek movies don’t

Though it was canceled in 1969, the syndication of Star Trek in the 70’s truly created the enduring widespread popularity of the show. As such, Paramount was totally excited about creating a new Star Trek TV show called Star Trek: Phase II. Now, this is where things just get insane: Leonard Nimoy was not going to appear in this version of Star Trek, and instead a full-blooded Vulcan named Xon (David Gautreaux, who later played an unnamed Starfleet officer in The Motion Picture) was to be the Spock replacement. The bald Deltan Ilia (Persis Khambatta) was also to be a regular character, along with the rest of the original series cast. Much of Star Trek: Phase II sounds a lot like The Next Generation: the first officer (Will Decker) would command more landing parties, there’s be children on the ship, etc. And in many ways, much of this version of Star Trek sounds awesome: there was a Pearl Harbor time-travel episode, Theodore Sturgeon was writing an episode, Janice Rand was back, etc.

Seemingly at the last minute, Paramount decided Star Wars and Close Encounters were making too much money and that the future of popular science fiction was in the cinema and not the small screen. Star Trek: Phase II became Star Trek: The Motion Picture and the rest is history. But if Star Trek: Phase II had happened, would it have been a hit? Would Star Trek have survived into the 21st century? Conventional wisdom says no. Until The Next Generation, part of what made up Star Trek’s identity was the relationship between Kirk, Spock, and Bones, something all of the classic-era movies inherently rely on. If Spock is absent and some guy named Xon is hanging out instead, it probably wouldn’t have worked. More Ilia might have been fun, but by the Seventies, Star Trek was ready to grow up, and the leap into the movies was probably the push it needed.

2.) A weird and wacky TNG features a hairy french captain, Patrick Stewart as Data, Marina Sirtis as Yar, and no Worf!

When you read about the early days of the development of Star Trek: The Next Generation, you quickly start to picture a very different TV show. Roddenberry wanted Picard to be French, complete with French phrasings and a delusional belief that the French invented everything. It’s almost impossible to imagine this version of Captain Picard. During intial casting, everyone on the TNG staff was in favor of Patrick Stewart…except Gene Roddenberry. To make things even weirder, longtime Star Trek producer Robert Justman originally wanted Patrick Stewart to audition for the role of Data.

Stranger still, Denise Crosby originally was supposed to be Deanna Troi, while Marina Sirtis initially read for Tasha Yar! Tim Russ (later of Star Trek: Voyager) auditioned for Geordi La Forge, as did Wesley Snipes! Worf was a last-minute character addition, which is strange since Worf ended up being in various iterations of Star Trek for eleven years! The Next Generation completely revitalized and re-contextualized Star Trek for the end of the 20th century and the beginning of the 21st. Despite its flaws, it seems like a miracle that it ended up as well-cast as it did. A TNG without Picard played by Patrick Stewart, and featuring a Wesley Snipes Geordi just seems wrong. Without the exact mix TNG had, Star Trek would have never made it out of the Eighties.

1.) Spock stays dead! So does Star Trek.

Prior to The Wrath of Khan being a bona fide hit, Leonard Nimoy’s relationship with Star Trek was pretty tenuous. He was barely convinced to be in The Motion Picture and only agreed to be in The Wrath provided he had story control AND on the condition that Spock would die. It’s really hard to conceive of a Star Trek movie after Spock dies where he doesn’t come back. Sure, Saavik is poised to sort of replace him, and David Marcus could have stayed on the ship to do science stuff, but it really doesn’t seem likely. The DC comic books of the 1980’s attempted to sort of come to grips with the concept of a Spock-less Enterprise, but the results read more like fanfic than real Star Trek! (And yet, super-entertaining)

The really interesting thing that happened post-Wrath of Khan is that Nimoy went from complaining about Star Trek to BECOMING Star Trek. After the second movie was a huge hit, Nimoy suddenly became Trek’s biggest advocate and went on to direct and co-write the next two films. And prior to the new J.J. Abrams Star Trek, the Nimoy-directed Star Trek IV was the highest grossing Trek movie ever! When you think about Nimoy’s involvement, enthusiasm and vision for Star Trek in the Eighties, it’s almost easier to imagine Star Trek without Spock than Star Trek without Leonard Nimoy.

Happy Star Trek Day, readers! Tell me below which of these alternate Trek dimensions is the most interesting, or chime in with your own below…

Ryan Britt is the staff writer for Tor.com. He’s not sure why September 8th isn’t a national holiday.