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Physics LibreTexts

19.12 UFOs

A majority of the U.S. public believe that aliens exist and they’ve already made contact. Fueled by reruns of The X-Files and Star Trek, and pervasive science fiction in the popular culture, most Americans are convinced that UFO’s are examples of alien visitation. Some also believe that a nebulous conspiracy at the top levels of the military and government has kept the secret for over fifty years.

There’s such a vast literature surrounding UFO’s, ancient astronauts, and alien abductions that there’s only room here for a pinprick in the balloon of speculation. The history of UFO sightings is instructive. A hundred years ago, UFO sightings were inspired by the fiction of Jules Verne and they took the form of flying airships and galleons. In 1947, a sighting by pilot Kenneth Arnold in Washington State, followed in 1948 by the infamous Roswell "incident," kicked off the modern UFO era. These UFO’s looked like sleek metallic flying saucers, a frontier technology of the time. People still report flying saucers, but after fifty years the sightings seem to have fallen into a rut, describing technology that seems retro and low-tech, almost corny. Most UFO sightings still occur in the United States, despite plenty of people in other countries who could be making sightings. Also, UFO sightings don’t occur randomly. It’s illuminating that major peaks have occurred at times of great tension in the Cold War or during pivotal events in the space program, such as the Soviet launch of Sputnik, the first Mars landing, and the Apollo moon program.

When a UFO can be identified, in most cases it corresponds to Venus, an aircraft, or a high altitude weather balloon. Visual observations are notoriously unreliable, and in the age of digital photography an image alone will never be decisive. But even when all conventional explanations, delusions, and charlatans are removed, there’s a persistent residue of cases with eyewitness testimony that’s hard to discount. Are they real visitations? Scientists are in a tricky situation when it comes to UFOs. Many think that the evidence of astro biology points to large numbers of habitable planets across the galaxy, and it follows that there’s a strong possibility of intelligent life out there too. But they’re utterly unconvinced by the evidence for UFOs. The sensible position is to insist on a high standard of evidence—images, eyewitness reports and vague conspiracy theories will not suffice. As Carl Sagan said "It pays to keep an open mind, but not so open your brains fall out.".

Why are some people so fervent in their belief in UFO’s? Planetary scientist David Grin spoon delved into this question by "consorting with the enemy," visiting UFO sites, investigating the bizarre phenomenon of cattle mutilation, and talking to the people who claim to be alien abductees. He has written eloquently about the bubble of belief that envelopes and sustains this culture, a place where skepticism and critical thought is in short supply. The gatherings have an evangelical fervor. Grin spoon also notes with disappointment that the stories are slightly shabby, like B-grade science fiction. Physicist Richard Feynman put it best: "The first principle is that you must not fool yourself and you are the easiest person to fool."

There must be deep psychological reasons why we want to believe in aliens. In western culture, aliens have been shape-shifting metaphors for the ills that lie within us. UFO’s can be found in medieval paintings and tapestries and throughout the Christian tradition. Many of these archetypes were contained in the classic 1956 science fiction movie, Invasion of the Body Snatchers. At the time, this story of pods from outer space that replicate and replace humans in a small Californian town was a thinly veiled commentary on the paranoia induced by Senator Joseph McCarthy and his Communist witch hunts. However, the film also embodied the tension between individualism and mindless conformity—people acting like "peas in a pod" and turning into vegetables. Conspiracy theories play into the same mindset. Superficially, it’s a reassuring explanation to suppose that we’re being buffered from the enormity of alien contact by the government or that a shadowy military-industrial cabal runs the world. But in fact conspiracy theories represent the ultimate abdication of personal responsibility. If you check your critical faculties at the door you’ve already voted with the pod people. Ideas like this endure because they’re self-reinforcing. Facts that fit the theory are admitted; facts that don’t fit are excluded.