“Where is everybody?” This is the question that physicist Enrico Fermi once asked colleagues over lunchtime in 1950. Fermi, known for his quick estimation skills, was shocked to find a discrepancy between the likelihood of extraterrestrial life and the lack of evidence for it. Thus, the Fermi Paradox was born.
Everything we have discovered so far suggests that life should be common in the universe. There’s nothing that makes us uniquely special – planets are prevalent, as is carbon, oxygen, and water. Organic materials have been seen on asteroids and in interstellar space. If this is the case, where are the other lifeforms?
There are many proposed solutions to the paradox. Some suggest that while the ingredients for life are common, actually getting them together to produce complex forms is extremely rare or even unique to Earth. Similarly, others suggest that what is rare is the "intelligent" bit of the mystery, rather than the complex part.
It's also possible that intelligent beings lack ways to communicate with us or they do so in a manner that we can't detect. Or perhaps we are in the early days of intelligent life's evolution in the cosmos. More pessimistic theories suggest that it’s in the nature of intelligent civilizations to destroy themselves before they become interstellar. Global warming, nuclear war, unstoppable epidemics due to antibiotic resistance – they don’t seem that unlikely, uh?
Probably one of the most fascinating possible solutions is actually older than the paradox itself. Russian astronautics pioneer Konstantin Tsiolkovsky implicitly mentioned the question in an unpublished manuscript. His solution is now known as the "zoo hypothesis". His theory suggests that alien civilizations exist, but they won’t contact us until we are ready to be contacted, leaving us to our own devices yet keeping an eye on us.
This idea clearly echoes in the minds of many when talking about UFOs. Many argue that alien sightings are just a way for these advanced civilizations to keep a non-too conspicuous eye on our planet. Many official investigations, such as Project Blue Book, have come to the conclusion that no UFOs were a threat to National Security – definitely in favor of the "good watchful aliens" idea. At the same time, the reports concluded there was no evidence that UFOs were actually extraterrestrials.
Project Blue Book was a series of systematic studies conducted by the United States Air Force from 1952 to 1969. The once top-secret investigations have now been dramatized in a 10-part series of the same name for HISTORY®. Project Blue Book starts on Tuesday, January 8, at 10 pm ET/PT.