Exactly 50 years ago, 2001: A Space Odyssey hit theatres, blowing the minds of moviegoers around the world. The product of a creative partnership between director Stanley Kubrick and science fiction luminary Arthur C Clarke, the film is widely recognized as one of the most influential works in cinematic history (just think how often The Simpsons has spoofed it; truly one of the best metrics of pop culture staying power).

As explored in depth in the new history Space Odyssey by Michael Benson, Kubrick’s goal with 2001 was to make “the proverbial good science fiction movie.” That culminated in a film that weaves together as many major sci-fi tropes as possible, such as artificial intelligence, human evolution, extraterrestrial contact, multidimensional gateways, determinism versus free will, deep space exploration, and the wisdom of manually-controlled airlocks.

But 2001 is also among the first hugely successful works based on the so-called ancient aliens hypothesis, one of the weirdest ideas to burst into the mainstream in the 1960s—which is saying something for a decade that collided the Space Age with the Psychedelic era. If you’re aware of the History Channel series Ancient Aliens or are a fan of the Stargate franchise, you probably know the gist: The hypothesis claims there is abundant archaeological and historical evidence to suggest that an intelligent alien civilization made contact with preindustrial humans and aided these societies in their technological and cultural achievements. Whoa dude.

It’s a viewpoint underpinned by the wild historical revisionism and newfound cosmic curiosity that defined so much mid-20th century science fiction. In 2001, it manifests as a giant black monolith that seems to inspire humans to push past tantalizing frontiers in space, intelligence, and reality (with mixed results for the humans).

The idea proved to be a fruitful hybrid of the mythological and science fiction themes that intrigued Kubrick and Clarke. It essentially involved replacing the roles of divine characters in the film’s namesake—Homer’s The Odyssey—and filling the vacuum with unknowable alien entities. Whether you believe in gods or aliens or neither, the profound feelings that these Odyssean tales evoke seems to spring from a common human premonition that we are not alone in the universe, and that our destinies have been shaped by inscrutable supernatural forces.

“Myths usually contain some kind of fact or reality to them,” space philosopher Frank White, author of The Overview Effect, told me over the phone. “What you see are entities that are more powerful and long-lived than humans, that appear to have the ability to come and go from the Earth at will.”

“The importance of 2001,” he said, is that “it raises these questions without necessarily giving a very linear or simple answer.”

That 2001 merges mythological narrative traditions with the extraplanetary awakenings of the Space Age was a sign of its times, and it’s worth noting that the film coincided with an explosion of cult interest in past alien visitation. It may have even played a role in launching the ancient astronaut hypothesis into the cultural space it occupies today, where it has become an unkempt tangle of pseudoscientific musings, conspiracy theories, and tacit admissions of underlying bigotry toward past cultures.

But what made 1968 such a fertile time for this previously fringe idea to hit the big time, and 50 years on, what does the meme’s mutation into a thousand different forms—from television series to UFO religions—imply about our perception of the past?

For starters, I should note that 2001 is by no means the first work to flirt with the allure of ancient aliens. The trope’s modern incarnation had crystallized as early as 1898, when Garrett P Serviss published the science fiction adventure Edison’s Conquest of Mars. In that tale, the characters discover that an advanced Martian civilization enslaved humans in antiquity, forcing them to build the Great Pyramids and shape the Sphinx in the image of their alien leader.

“Here, then, was the explanation of how those gigantic blocks that constitute the great Pyramid of Cheops had been swung to their lofty elevation,” Serviss’ narrator explains. “It was not the work of puny man, as many an engineer had declared that it could not be, but the work of these giants of Mars.”

This premise that we “puny” humans required an assist from “giants” to reach a higher intellectual plane was subsequently expanded upon by many authors in the 20th century, including HP Lovecraft, Kurt Vonnegut, and of course, Arthur C Clarke, whose fascination with the hypothesis predated his collaboration with Kubrick by many decades. Over email, Michael Benson told me that Clarke mentioned, in a 1963 letter to astronomer Carl Sagan, the “extraordinary cases” collected in Charles Fort’s “peculiar book” Lo! That book, published in 1931, is one of the earliest nonfiction works to riff about ancient astronauts.

“Both Clarke and Carl Sagan entertained the idea that aliens may have visited Earth during ancient times,” Benson said, noting that Clarke was especially impressed by cave paintings in Tassili n'Ajjer as potential evidence of such encounters.

Cave art at Tassili n'Ajjer . Image: Patrick Gruban

However, Benson noted that Clarke and Kubrick were “keenly aware” that “there was a quack fringe out there that credulously believed in almost every supposed example of such contact, in effect giving more serious investigators and thinkers a bad name.” Early in their partnership on 2001, Clarke even credits himself with saving Kubrick from the “gruesome fate” of “believing in flying saucers.”

Despite the careful skepticism, the mood in the late 1960s was clearly ripe for this mind-boggler of a hypothesis to make a broader memetic debut. In the same year that 2001 hit theatres, Erich von Däniken published his bestselling book Chariots of the Gods? which argues that archeological achievements like the Pyramids of Giza, Stonehenge, the Nazca Lines, or the Moai on Easter Island were a result of interactions with an alien intelligence.

The thrust of his case is that ancient societies produced many similar artifacts, images, and stories that could be interpreted as representations of extraterrestrial beings. The thesis struck a chord with the public, but the academic community has generally dismissed von Däniken’s work as wacky pseudoscience at best and pernicious ethnocentrism at worst.

“I understand where these theories come from,” Jens Notroff, an archaeologist at the German Archaeological Institute, told me over Skype. “I read von Däniken when I was a teenager and it is fascinating. It’s cool to see all these links between different cultures and places.”

“It only took me seven years of university courses to see that it’s not that easy,” he continued. “Of course, it looks easy if you cherry-pick a few symbols and phenomena. Then, you can make a match. But if you look closer, you see that human culture is so much more complex.”

In addition to these doubts about its scientific merit, critics have also suggested that the ancient aliens hypothesis has racist undertones. Anthropologist Kathryn Denning, a York University professor with a background in both archeology and SETI, points out that these ideas often gravitate toward the achievements of American indigenous or African civilizations.

“To suggest, for example, that Machu Picchu couldn’t have been built by humans is really insulting to humans,” she told me over the phone, “and specifically insulting to the humans who demonstrably did build it."

The notion that some societies in particular were not sophisticated enough to achieve such impressive works, necessitating some kind of extraterrestrial explanation, is woven into the core of the ancient aliens idea, Denning said. “Of course, the other logical possibility, and the correct one, is that they were sophisticated enough to do what they did, and that our erroneously low estimation of their sophistication is the problem,” she added.

Notroff called this dark edge of the ancient aliens trope “dangerous.” “If we allow racism to creep into this kind of pop culture, it becomes much more acceptable in everyday narratives,” he said.

These are strong critiques, but to be fair to believers in ancient aliens, there are plenty of unresolved questions about ancient peoples and the material creations they left behind. Who knows? Maybe those symbols and myths are bonafide records of aliens showing up at Earth because humans were having such a pathetic go of it.

Of course, this opens up the realm of “maybes.” Maybe aliens created our civilization. Maybe interdimensional beings are influencing our brains. Maybe we are in a dog’s dream. They are all possible, but as Notroff points out, it gets problematic when evidence is selectively chosen or omitted to reinforce an extreme viewpoint—especially one that can be a vector for prejudice—instead of letting theories be shaped by the hopelessly messy data that is endemic to humans.

Perhaps it’s that very messiness that attracts people to a simplified explanation like the ancient astronauts hypothesis. One reason that 2001’s monolith remains such a timeless representation of alien life is that, despite its enigmatic form, it seems to have a straightforward agenda: Step 1) Inspire these primates to start thinking about planetary domination. Step 2) Lure these primates to alien worlds like the Moon. Step 3) Get at least one of these primates to a Star Gate near Jupiter. Step 4) Star Child.

In this way, the film envisions a clear determinist timeline of human evolution that absolves our species of any credit or blame for our past technological progress or our ultimate future destiny. Kubrick and Clarke used that lack of agency to amplify the mythological undercurrents of 2001, drawing an analogy between protagonist Dave Bowman and his crew, who are inexorably at the mercy of alien and robotic intelligences, to Odysseus and his crew, who are hamstrung by the unpredictable whims of the gods.

That alluring fantasy of dodging responsibility for our own development is at the heart of the ancient astronaut hypothesis. It is a testament to the concept’s resilience that despite the immense skepticism leveled at it, the idea has not only survived the last 50 years, it has exploded into a viral ideology with the multi-tentacled reach of Cthulhu, the most famous of all Lovecraftian “Great Old Ones”—a fictional form of ancient aliens.

In Denning’s view, this enduring appeal might be linked to a mass denial about the complexity of our origins and the uncertainty of our future. “What does [the ancient aliens trope] say about our engagement with ourselves?” she asked. “We are completely overwhelmed by ourselves, and also maybe on some level, afraid of our own power.”

That sense of anxiety has ratcheted up over the past 50 years as profound existential challenges, such as climate change and nuclear sabre-rattling, develop with ominous clarity. Those of us with internet access are constantly inundated with new problems—melting polar caps, political instability, enormous wealth and technological inequality. As a result, it can be jarring to look back to past civilizations, clearly built by smart, industrious peoples, and see that they often did not overcome the pressures of their own times.

“People have a hard time facing the awesomeness of ancient civilizations because they view them as collapsed and gone,” Denning said. “When you look at something that was amazing, and there’s nobody there anymore, you have to acknowledge your own mortality, and the mortality of your civilization. People don’t like doing that. They will try really hard to not do that.”

Notroff likewise emphasized a connection between the popularity of the ancient astronauts hypothesis and modern insecurities about the direction of our lives, and our species. “I think it says more about us than these prehistoric people,” he told me. “There seems to be some deeply rooted wish for the supernatural. We’re not living in particularly religious times, but I think it’s a projection of a lot of peoples’ wishes to leave control to someone else.”

The impulse to avoid existential angst by appealing to the divine is nothing new for humanity, but 1968 was clearly a watershed year for expanding its spatiotemporal dimensions. Moulded by the geopolitical tensions of the Cold War, the awe-inspiring feats of the Space Race, and the emergence of civil rights movements, the late 1960s were a time of momentous change and instability on Earth, twinned with the first direct human exploration of the universe beyond it.

2001 and Chariots of the Gods? are reflections of a culture that was hungry to impose its mythos beyond the recently broken barriers of the sky, with the hope that those frontiers might finally dispense the wisdom that could help “usher us into species-wide maturity” that Clarke longed for, Benson said.

“And of course, that's the theme of 2001,” he told me, “the trajectory ‘from ape to angel,’ as Kubrick put it.”

In retrospect, it’s fascinating that 2001 grappled with human limitations in the face of more advanced forms of intelligence, at the same time that the ascendant ancient aliens hypothesis revealed that humans can’t even be trusted to identify our own intelligence when it stares at us across time.

There’s no question that ancient cultures told riveting tales of supernatural beings and alternate dimensions, and expressed themselves through a breathtaking range of creative works, from towering monuments to meticulously crafted fine art. That this material inheritance from our ancestors is often chalked up to extraterrestrial intervention demonstrates a reluctance to recognize the native genius of humanity—perhaps because that genius failed to save past cultures from suffering, death, and collapsed civilizations.

There is a symbolic echo of this need for intimate self-evaluation in the final scenes of 2001, in which Bowman confronts doppelgängers of himself at various life stages, leading to his rebirth as a transcendent post-Earth entity. The film is purposefully ambivalent about drawing clear conclusions, allowing many interpretations to abound, so maybe one reading of that last sequence is that Bowman must face his past and future selves to achieve cosmic deliverance, and that humanity must do the same on a species-wide level if we are to be saved from ourselves.

After all, tales of ancient aliens are “inescapably and always about us,” as Denning put it. “On the discourse and cultural level, I think this is ultimately all about people reckoning with the ‘other,’ and who the ‘other’ is gets pretty mixed up and confused because we don’t think straight most of the time,” she said.

“That’s just humans.”