They may already be dead or hidden, but a new study has arrived suggesting that intelligent extraterrestrial civilizations are likely to exist throughout the universe, extinct or otherwise.
As explained by Space.com, professor Adam Frank and Woodruff Sullivan looked at the probability of alien civilizations forming on habitable planets. They modified the Drake equation into what they call an “archaeological version, “ essentially removing the final part of the equation that involves the “length of time for which…civilizations release detectable signals into space.”
In doing so, they found that technologically-advanced aliens “very likely evolved before us.” In fact, Frank says, “It is astonishingly likely that we are not the only time and place that an advanced civilization has evolved.”
“…unless the odds of advanced life evolving on a habitable planet are astonishingly low, then human kind is not the universe’s first technological, or advanced, civilization.” – Are we alone? Setting some limits to our uniqueness
And yet, there’s also a very good probability that we’ll never cross paths with those aliens. Like I said, nearby civilizations may already be dead, sending out no signals or other signs that they ever existed. That, or they may be around only after we’re extinct.
The universe is big, and we’ll have to navigate those obstacles of time and space before we truly get to the bottom of this question.
On the other hand, a study from last year suggested that advanced alien civilizations are “very rare or entirely absent from the local universe.” However, the study looked only for the waste heat emissions of Kardashev Type III civilizations, or those able to harness energy on a galactic scale.
According to Phys.org, we humans aren’t even a Kardashev Type I civilization, meaning we haven’t fully harnessed the power of our own star. We have a ways to go, but that also means alien civilizations in nearby galaxies may be in the same position on the Kardashev scale, and we cannot detect them using these methods. Not yet.