In May, Congress made a fitful, unsatisfying attempt to reveal what the government knows about what we are now calling “unidentified aerial phenomena,” but which used to be known as UFOs. It already seems to have been forgotten about, alas. But others continue to ponder the possible implications of extraterrestrial life at a more theoretical level.
At Reason, Ron Bailey reports on an article in the Proceedings of the Royal Society by astrobiologists Michael Wong and Stuart Bartlett that attempts to answer the question that has baffled scientists (who tend to discount virtually all “evidence” that is offered as proof of extraterrestrial life): Where are the aliens? First formally pondered by Enrico Fermi, the conundrum, now stylized as the “Fermi paradox,” wonders where all the aliens in our galaxy are if they are sufficiently advanced to travel the stars. My favorite “solution” to this is the “Zoo hypothesis,” which posits that humanity is deliberately insulated from interstellar goings-on because we are insufficiently advanced. Wong and Barlett offer two different explanations: Their civilizations either grow so large and complex as to become unsustainable, or those in charge of said civilizations realize their unsustainable course and restrain it, thereby stalling the kind of development that would beget spacefaring. As Bailey puts it, “No alien visitors to Earth have been detected because they either destroy themselves or they choose to stay quietly at home.” He is right to note a kind of xeno-Malthusianism to this.
But if another study is correct, even if we do encounter some extraterrestrials, we might not need to be that worried about them. Vice reports on a paper by Alberto Caballero, a Ph.D. student at Vigo University in Spain, that attempts to estimate the number of potential hostile extraterrestrial civilizations in the Milky Way galaxy. His conclusion:
Caballero concludes that the probability of a hostile alien race invading Earth is low—very low. “The probability of extraterrestrial invasion by a civilization whose planet we message is, therefore, around two orders of magnitude lower than the probability of a planet-killer asteroid collision,” which is already a one-in-100-million-years event, he writes in the paper.
He also said that there is likely fewer than one malicious extraterrestrial civilization in the Milky Way that has also mastered interstellar travel, which would make them a so-called “Type 1” civilization.
Caballero makes what he admits are some “questionable” assumptions in his paper, basing it on Earth’s history and how life is known to exist; another world’s history or other forms of life could confound his findings.
At any rate, for now, it’s all just speculation. Unless (or until?) the next UAP hearing reveals unexpected information — or an unanticipated guest.