So just how many alien civilizations are out there in the vast expanse of space? Let's do some number-crunching.
In the universe imagined by Gene Roddenberry's "Star Trek" series and its many spinoffs, extraterrestrial life is everywhere. In fact, science fiction has trained us all to think that our galaxy is crawling with life-forms, many of which are intelligent and similar to us.
So far, science reality, however, has told a different story. After a half-century of searching for alien civilizations, the result is zilch. And now, a new paper published by three researchers at Oxford University casts serious doubt on "Star Trek's" picture of a crowded universe.
The authors begin by reevaluating what's known as the Fermi Paradox, which notes that even though an intelligent civilization should be capable of building colonies throughout the Milky Way galaxy in just a few tens of millions of years, we've never heard a peep from anybody.
Put simply, the Fermi Paradox asks: "Where is everybody?"
In their paper, the researchers at Oxford argue that the paradox is built on a false expectation: that intelligent life is a common occurrence. But is it?
In 1961, astronomer Frank Drake proposed a way of answering that question. In what's called the Drake Equation, he multiplied the probability of life evolving by the likelihood of life developing the intelligence necessary for interplanetary travel and communication. The result of the equation, of course, depends on which numbers of probability you plug in.
Most people who use Drake's equation assume that the appearance of life and the development of intelligent life are common phenomena. When those assumptions are multiplied, they estimate hundreds or even thousands of extraterrestrial civilizations should be in our galaxy alone!
It's those assumptions that the Oxford scientists are questioning in their paper. In other words, what if intelligent life isn't common at all?
As Seth Shostack, senior astronomer at SETI, recently pointed out, we may be dramatically overestimating the probability of life arising on other planets. Maybe "no one has colonized the galaxy," he writes, "because no one else inhabits it."
And that might even understate the problem. Given what we know about the conditions required to support living things, the Oxford scientists estimate that there's at least a 53 percent chance we're alone in the Milky Way, and at least a 40 percent chance that we're the only intelligent civilization in the known universe! And even that estimate may be too generous.
As Guillermo Gonzalez and Jay Richards write in their book, "The Privileged Planet," the fact that the conditions necessary for life exist on even one planet is a statistical miracle. That those conditions might exist somewhere else, let alone that extraterrestrial organisms there would evolve the brain power necessary to travel the stars—is—there's no other way to put it—astronomical.
Now of course, SETI stands for "Search for Extraterrestrial Intelligence," and Shostak may want to keep his job. So he punts, assuring readers that with further exploration, we may very well find life on other planets or moons within our lifetimes, thus rewriting our expectations about alien civilizations.
But folks, this is a worldview talking, not evidence. The search for extraterrestrial life is fueled in large part by a materialist assumption that life on this planet is nothing special.
Of course, the Scriptures don't necessarily teach that God didn't create life anywhere else in the universe. That possibility—however remote—shouldn't bother us at all. But for the materialist, who sees all of life as a cosmic accident, there are few things scarier than the thought that our planet is the only place ever to play host to an intelligent species—not because they're afraid of a quiet universe, but because of how loudly such a universe would proclaim that Someone actually put us here.