Looking at the title, I would imagine the first question most of you have is… how do they know? Did someone accidentally dial into a massive Zoom call between the White House and all of these civilizations where they were planning which humans to abduct next? Nothing quite so flashy or definitive, I’m afraid. A recent article at Forbes is describing the findings in a report published in The Astrophysical Journal where a group of scientists has run the numbers and concluded that there are probably 36 different Communicating Extra-Terrestrial Intelligent (CETI) civilizations in our galaxy. And if conditions can be expected to be the same everywhere, given the staggering number of galaxies we’ve found in the universe so far, intelligent, technologically advanced civilizations are more common than hair lice in a kindergarten class.
It’s the oldest and the greatest cosmic question of all: is there anybody out there?
For years all we’ve had is the Drake Equation to help us understand the question, but no indication of an answer. Now a group of scientists at the University of Nottingham think they’ve come up with a new “cosmic evolution”-based calculation—or, rather, an estimation—that suggests that there are likely to be at least 36 ongoing intelligent civilizations in our Milky Way galaxy.
The Milky Way, home to our Solar System, is estimated to have 100 billion to 400 billion stars, and roughly one exoplanet per star in our galaxy.
Published today in The Astrophysical Journal, the new paper examines the likely number of Communicating Extra-Terrestrial Intelligent (CETI) civilizations in the Milky Way. It assumes that intelligent life comes to occur on other planets much as it has done on our own planet.
Before we get too excited, this prediction is essentially based on nothing more than guesses. And they’re the same guesses we’ve been using for ages, leading us originally to the Drake Equation. Scientists working in this field have the luxury of tossing out theories like this because there’s absolutely no way of proving or disproving them and there likely won’t be in their lifetimes.
This latest theory is based on a wild number of assumptions. And other authors at the same outlet have already pointed out that it’s a preposterous number of assumptions, most of which are easily challenged. The first assumption of note is that they’re calling for an average of one planet per star. If Kepler taught us anything, it’s that planetary formation during the birth and evolution of a star is almost a given. The longer we stare at the stars and the closer we measure their movements, it seems likely that the number is probably considerably higher.
The next quirk of this theory is that it limits the possibility of life to only rocky worlds similar to ours that are orbiting yellow stars that are like our own sun. These are the usual blinders that scientists wind up wearing because we thus far only have one example of life in the universe to study and that’s on Earth. For all we know, life could exist in the atmosphere of gas giants or on nearly airless, tiny worlds like Mercury. Some have already speculated that life exists and could even evolve in the vacuum of space.
This team also assumes that a planet will take 4.5 billion years to evolve technologically advanced life because that’s how long we think it took here. That’s a rather anthropocentric approach to the question, isn’t it? Again, we’re basing everything on a sample of one planet. The galaxy (and the universe) could be simply lousy with life. Or maybe there’s nobody out there. We won’t know for sure until we find them.
Personally, I still prefer to believe that there are plenty of intelligent lifeforms out there. And while we have zero evidence to prove it definitively, I suspect that some of the recent “activity” we’ve seen in our airspace suggests that at least some of them have found their way to our planet. At this point, it’s probably the biggest question I’m craving an answer to before I shuffle off this mortal coil.