Science-fiction lore has long been punctuated by a perceived wall of separation between “Star Wars” and “Star Trek,” the genre’s two most successful and enduring franchises. While most outside observers wouldn't know a Wookie from a Klingon if one came up and bit them, die-hard fans understand that the two universes couldn’t be more different: “Star Wars” is an action-packed space opera, while “Star Trek” is a cerebral allegory on society’s ills. Where is the confusion?

But news last week that J.J. Abrams is officially on board to direct Disney’s (NYSE:DIS) “Star Wars VII” promised to restore balance to the universe -- in an Anakin Skywalker kind of way. Abrams, of course, successfully brought the aging “Star Trek” franchise back from the dead with his 2009 reboot, and he has agreed to try the same thing with “Star Wars,” which still hasn’t fully recovered from creator George Lucas’ misguided, CGI-laden prequels.

But many “Trek” fans aren’t so sure about seeing the savior of their beloved franchise cross over to the dark side. Jordan Hoffman, an avowed “Star Trek” fan and author of the Badass Digest blog, tweeted that “I feel like J.J. Abrams took me out to the prom but left with the hotter girl.” The quote was later passed around on various blogs -- including Mashable and -- suggesting that perhaps Hoffman was not alone in his uneasy feeling.

And he’s not. Amid the excitement that spread across the Twitterverse over Abrams’ upcoming “Star Wars” gig this weekend, fans of both franchises expressed dismay over the unification of two divergent sci-fi visions. “You can’t direct both ‘Star Wars’ and ‘Star Trek,’” posted Twitter user Charlie Moreno. “I’m 99.9 percent sure the universe will explode.”

Some entertainment bloggers echoed those concerns, albeit more eloquently. “One of the biggest concerns among certain segments is having the same guy behind ‘Star Trek’ taking over ‘Star Wars,’” wrote Indiewire’s Drew Taylor, who added that “Abrams will want to put a new visual stamp on this franchise not only to assuage fans, but to honor where the series has been while also taking it in a new direction in addition to ensuring it stands apart from Captain Kirk and the gang.”

To be certain, the geekosphere contains its share of crossover fans who believe the universe is big enough for the U.S.S. Enterprise and the Millennium Falcon, but some sci-fi enthusiasts who straddle that line simply contend that, under the same director, the two franchises will not retain their distinct aesthetic styles. “Even if they were not so distinct in outlook, it is troubling to see both franchises placed in the hands of one man,” Huffington Post blogger Richard Berry wrote. “This is like Alex Ferguson becoming manager of Manchester City as well as Manchester United.”

Twitter user Khara House perhaps summed up such objections best: “Dear JJ Abrams: If I wasn't a fan of [both] I’d totally be calling you a traitor right now,” she tweeted on Sunday.

Despite the outcry, “Star Trek” and “Star Wars” are not as mutually exclusive as fans would like to believe, at least not in a commercial sense. Indeed, the two franchises have more or less fueled each other’s success. The original “Star Trek” series, despite a passionate fan base, was short-lived, running only three seasons before being canceled for low ratings in 1969. A few years later, though, the series influenced a young George Lucas when he was writing early drafts of “Star Wars.” Consequently, it was the enormous success of Lucas’ “Star Wars” in 1977 that helped convince studio heads at Paramount that “Star Trek,” too, could work on the big screen. The first “Star Trek” film was released two years later, and the two franchises have been intermittently dueling it out on the big and small screens ever since.

Whichever franchise you’re partial to, it’s clear that the science-fiction ecosphere works best when they exist in tandem, and who better to keep that symbiotic relationship going than Abrams, one of the genre’s most prolific directors? So all you naysayers out there, put away your phasers or blasters or whatever.