In a 1950 discussion with colleagues on the subject of the possible existence of extraterrestrial life, famed physicist Enrico Fermi asked, “Where are they?”
It is not an unreasonable question.
Fermi’s Paradox lies in the contradiction between high estimates of the potential numbers of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations.
If Earth’s life-development timeline is typical—when taken in the context of the billions of years that came before we showed up—the age of the universe, and its vast number of stars, suggest extraterrestrial life should be common. So withstanding the multitude of UFO sightings, where’s the hard evidence that would surely be visible in the form of spacecraft or probes, if the galaxy were teaming with life.
There are several gaps in this logic, one being that all UFO sightings are either hoaxes or misidentified natural phenomenon. Even the US Air Force’s Project Blue Book found a small percentage “inexplicable by contemporary technology.” If even one sighting was real, the paradox evaporates.
But for arguments sake, let’s say every UFO sighting in history has been terrestrial in origin. What are the other holes in the argument?
One is the Zoo Hypothesis. Essentially it postulates that earth-space is a sanctuary. Much like a wildlife refuge, it is to be left unmolested and unaltered by external cultures and technologies; allowed to develop on its own course and of its own volition. Under this hypothesis, aliens may be among us now. Unobserved they could be wandering our very streets, homes and bedrooms (or not, hopefully they have a sense of propriety).
Actually a great deal of the Fermi Paradox evaporates at the very idea that aliens could walk around undetected by our current technology.
Walk around undetected? Sounds like paranoid conspiracy theorist fodder. Maybe not, when you consider how close we are to realizing that ability.
We humans, barely a century from our first forays into the air, and mere decades since first breaching our atmosphere into local space, are already pondering invisibility cloaks rendered through the employment of metamaterials. While a hundred years seems like a long time on a human timescale it is less than a blink of the eye on a geologic timescale. Even less than that on an astronomic timescale.
Most of us grew up in the space and information age. We believe we know what’s out there and surely must know what is in our solar system. In this time-lapse computer animation, produced by Scott Manley, we humans look like cavemen shining our light of discovery upon our solar neighborhood. Watch the video; you’ll be amazed at how little we knew about our solar neighborhood a few years ago, much less in Fermi’s time.
The rendered asteroids are mostly 100 meters or larger. By the end of the animation there are roughly half a million asteroids. Current scientific estimates place the number of asteroids 100 meters or bigger at half a billion. That’s billion with a B. That means there’s a thousand times more football-field-sized asteroids than have been found to date.
Consider for a moment, that in 2013 there remains roughly 499.5 million undiscovered football-field sized asteroids in our neck of the woods. How much water does Fermi’s 1950 assertion hold, when, even today, we can’t say there aren’t (potentially cloaked and potentially smaller than a football field) alien ships visiting.
In that light, it doesn’t seem like much of a paradox.