Researcher Estimates That There Are 4 ‘Malicious Extraterrestrial Civilizations’ in Our Galaxy

Stephen Hawking once famously warned that transmitting information from Earth into outer space may lead to the extinction of human civilization. “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 Native Americans,” he exclaimed.

The remarks of Stephen Hawking have often been used to dissuade people from engaging in METI, which stands for Messaging Extraterrestrial Intelligence. But how many “evil” extraterrestrial civilizations are there out there? And what are the possibilities that a wicked extraterrestrial culture somewhere in our galaxy would pick up on any message that we sent out into our galaxy? There has been little to any study done on this subject, and just a handful of experts have even ventured a hypothesis about it.

The purpose of a new thought experiment is to at least make an educated estimate in the hopes that other scientists will start taking METI more seriously and will seek to assess how perilous it truly is to try to make contact with extraterrestrial civilizations. You can read the paper for yourself here.

According to the findings of this study, which the author of the article acknowledges has “some limitations,” the Milky Way is home to around four “malicious alien civilizations.”

The paper, titled “Estimating the Prevalence of Malicious Extraterrestrial Civilizations,” was written by Alberto Caballero, a PhD student in conflict resolution at the University of Vigo in Spain. Caballero also authored a separate study published in Cambridge University’s peer-reviewed International Journal of Astrobiology earlier this month that tried to analyze the origin of the WOW! Signal.

According to Caballero’s findings, the likelihood of a hostile extraterrestrial civilization conquering Earth is low—extremely 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,” he posits in the paper, which is already an occurrence that occurs once in 100 million years.

He also stated that there is probably less than one malevolent extraterrestrial civilization in the Milky Way that has also mastered interstellar travel, which would make them a “Type 1” civilization. Type 1 civilizations are considered to be advanced and pose the greatest threat to humanity.

“0.22 Type-1 civilizations (capable of nearby interstellar travel), and 4.42 civilizations if all of them were like humanity (we aren’t a Type 0 yet),” he said. “I don’t mention the 4.42 civilizations in my paper because 1) we don’t know whether all the civilizations in the galaxy are like us (below Type-0), and 2) a civilization like us would probably not pose a threat to another one since we don’t have the technology to travel to their planet (we will reach that technology once we become a Type-1).” He wrote.

According to Caballero, there have been fewer invasions as humanity has gotten more evolved. This suggests to him that extraterrestrial civilizations capable of destroying Earth would be less interested in actually doing so as they improve technologically.

“I did the paper based only on life as we know it. We don’t know the mind of extraterrestrials. An extraterrestrial civilization may have a brain with a different chemical composition and they might not have our empathy or they might have more psychopathological behaviors,” he tells MotherBoard. “I found this way to do [the study], which has limitations, because we don’t know the mind of what aliens would be like.”