Searching for intelligent life on Earth and beyond

Bismillah Assalamu Alaikum


Sometimes I wonder if Earth’s leading candidate for an “intelligent” species, is really any smarter than yeast. For the purposes of this post, however, I’ll concede that humans qualify as intelligent, because my subject today is extraterrestrial intelligence. Does our failure to find even one other civilization in the cosmic expanse tell us anything about the chances our civilization will survive? It just might.
When it comes to searching for alien civilizations, scientists are of two minds. Their intellectual curiosity spurs them to make extraordinary efforts not only to discover such civilizations but to make contact. But their cautious nature causes them to worry about the consequences. The Voyager space probes contain messages to aliens about our civilization, even maps that could lead them back to our planet. And in addition to the outpouring of radio and television transmissions we inadvertently send into space, some scientists have purposely transmitted messages to deep space in an attempt to make contact with aliens. However, no less an authority than Sir James Lovell, founder of the Jodrell Bank Observatory, reportedly said about aliens who might receive such messages, “It’s an assumption that they will be friendly — a dangerous assumption.” Others have echoed his concerns. Our own planet’s history of first contacts between civilizations should give us pause about contacting extraterrestrials. As Stephen Hawking puts it, “If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the American Indians.” A “visit” by a sufficiently advanced civilization might not be distinguishable from an invasion.

But it’s not alien invasion that is my concern; it’s The Fermi Paradox. In 1950, Enrico Fermi, Nobel prize-winning physicist, responded to those who suggested the odds were high that there were other civilizations in the universe, “So, where is everybody?” In other words, if all it takes to develop intelligent life forms is a universe billions of years old, mind-bogglingly huge, and full of so many galaxies, stars, and planets that we can’t count them, then there should be alien civilizations all over the place and by now we should have conclusive evidence of their existence. Yet there’s no such evidence. That’s The Fermi Paradox. Some will claim that UFO reports prove the existence of ETs. They don’t. Conclusive evidence would be things like intercepting transmissions incontrovertibly from intelligent ETs, better yet, exchanging messages with an alien civilization, or best, an alien landing party that makes itself available for media interviews, meetings with world leaders, and medical exams. Not likely. Nor is it likely there really are captured flying saucers and alien corpses in Area 51, in spite of claims from the UFO crowd.

In the years following Fermi’s question, scientists have refined their calculations of the likelihood there’s intelligent life in the universe. Perhaps the best known equation is the one developed by astronomer Frank Drake in 1961. The Drake Equation focuses on our own galaxy, the Milky Way (illustrated above), since it’s plenty old enough (over 13 billion years), big enough (100,000 light years across by 1,000 light years thick), and crowded enough (over 200 billion stars) to harbor intelligent life. Our civilization is proof of that. Depending on the values one plugs into each of the factors in the equation, estimates vary from as low as 10 to as high as 20,000 “communicative” civilizations in just this one galaxy. Drake himself came up with an estimate of 10,000 civilizations. At that rate, there would be many, many more in the billons of galaxies beyond ours. Astronomers have watched the skies through optical telescopes for centuries, seeking evidence of intelligent life. More recently, SETI (search for extraterrestrial intelligence) has utilized radio telescopes to sample the wide electromagnetic spectrum in hopes of intercepting intelligent transmissions. There’s no conclusive evidence to show for these efforts. “So, where is everybody?”

What worries me about The Fermi Paradox is one of the possible answers. The reason we have not found any evidence of exterrestrial civilizations is that in every case they have been destroyed too soon for that to occur. Maybe there’s a “cosmic roadblock” that no civilization has been able to overcome — comet and asteroid impacts, solar flares, gamma ray bursts, and other external threats, or volcanic eruptions, extreme changes in the atmosphere and climate, magnetic field shifts, plagues, and other threats on their home planets. Even worse, some fear, is the possibility that as civilizations advance, there is an inherent risk that they will ultimately destroy themselves — through overpopulation, exhaustion of planetary resources, out-of-control technology, and warfare. If so, our failure to find evidence of intelligent life in the universe would mean that the odds of our own civilization surviving are slim. (Click here for evidence that our civilization is indeed destroying itself.)
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