there are four ‘malicious alien civilizations’, scientists say

4 mins
27 May 2022
there are four ‘malicious alien civilizations’, scientists say

But don’t worry, they probably don’t care enough to kill us!

image Men in Black

words Louis Staples

A very clever man named Stephen Hawking, who you might have heard of (he’s a big deal, apparently?) once said that trying to communicate with aliens by sending messages into deep space might lead to the destruction of human civilization. Fun!

The warning went: “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.”

Hawking’s prediction, plus the many blockbusters which forecast a similar scenario, means the practice of Messaging Extraterrestrial Intelligence (METI) is fairly controversial. Wouldn’t it be typical if being a “pick me” species, and shitposting into space, led to the extinction of humans? But also, what if he’s wrong? We might miss out on a huge discovery.

Part of what makes this such a hot topic is that, really, we know very little about how many alien civilisations there could be in the universe. And we know even less about whether they hate us and want us dead, whether we give them the ick, or whether they think we’re irrelevant and tacky.

In exciting news, Vice reports that a new experiment is trying to formulate a rough idea of how many alien civilisations there are in the Milky Way. The hope is that doing so will allow scientists to work out whether it’s actually dangerous to contact other civilisations, which may or may not be out there. Then they’ll know whether they should abandon METI, or ramp it up a notch.

According to this paper, there are roughly four “malicious extraterrestrial civilizations” in the Milky Way. The paper, which its author admits has some limitations, found that if we sent out 18,000 messages to different planets in our galaxy, then the likelihood of one of them leading to our destruction would be very small. (In fact, we’d still be more likely to be wiped out by an asteroid).

The paper is called “Estimating the Prevalence of Malicious Extraterrestrial Civilizations". It was written by Alberto Caballero, a PhD student in conflict resolution at the University of Vigo in Spain. He also authored a separate study, published in Cambridge University’s peer-reviewed International Journal of Astrobiology earlier this month, which attempted to analyse where the famous WOW! Signal originated.

Caballero admits it’s pretty difficult to know if his calculations are correct, because he had to make some assumptions while carrying out his research. (And guesswork is generally the enemy of exact science). His research was based on how many “invasions” there have been on Earth, applied to the number of known habitable exoplanets. (According to Italian SETI scientist Claudio Maccone, there could be as many as 15,785 civilizations in the Milky Way).

Still, Caballero concludes that a hostile alien race invading Earth is very unlikely. "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 also said that, while there might be more civilisations in the Milky Way, it’s unlikely all of them will have mastered space travel to the level to be able to mount an invasion. (He calls these Type 1 civilisations).

“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).”

Despite Russia’s attempted invasion of Ukraine this year, the trend on Earth is that, when societies become more advanced, the number of invasions decreases. Therefore, Caballero suggests that alien societies advanced enough to invade Earth might not be interested in doing so.

“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 behaviours,” he told Vice. “I found this way to do [the study], which has limitations, because we don’t know the mind of what aliens would be like.”

Still, even Caballero admits he might be wrong here. So, basically, it’s not clear whether we’re any closer to knowing if Hawking was right about METI, or how many aliens out there want to kill us.

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