The Milky Way Contains 36 Contactable Alien Civilizations, Scientists Estimate. Here’s the problem: It’s pure guesswork. Excerpt:
Westby and Conselice present a revision of the Drake equation that loops in new findings from “a mixture of areas of contemporary astronomy,” according to the study. For instance, thousands of exoplanets have been detected in alien star systems over the past two decades, so Westby and Conselice included data about the odds that worlds orbit their stars within the habitable zone where liquid water can exist. The team also focused on the timescale of intelligent life’s emergence on Earth, a process that took about 4.5 billion years.
The pair’s results produced a range of possible CETI populations that currently exist in the Milky Way, with four at the low end, 211 as an upper limit, and 36 as the most likely figure based on the team’s assumptions.
These high numbers may sound like great news for alien enthusiasts, but Westby and Conselice caution that even if their estimate is correct, CETI worlds may be too far away from Earth to establish communication. If 36 contactable civilizations were scattered throughout the galaxy, they would be about 17,000 light years away from our planet on average, a distance that would require at least 34,000 years for a two-way conversation.
I’d be the most amazed person on the planet if somehow someone could establish that there are no intelligent species out there, somewhere, in the billions of planets that certainly exist in our galaxy. But the Drake equation and this update of it are based only on assumptions; the only solid basis this thesis has at all is the estimated number of exoplanets in our galaxy, which again, is an extrapolation built on a very small sample.
And when we talk about communicating, well, there’s no guarantee that any alien species would even use a form of communication we could detect, let alone understand, or that they’d even be similar to us enough culturally as to allow any social interaction at all.
I’ve cranked out a fair amount of science fiction myself. Alien intelligence is almost a necessity of sci-fi; the only major series I can think of that did without it was Asimov’s Foundation series and its two sister series, the Empire and Robot books. But that’s fiction. And this is guesswork. It’s kind of sad, but there you are.