There are perhaps four potentially hostile civilizations in the Milky Way that might attack humanity if we continue to send out communications to aliens, according to an astronomer.

We reported last month that scientists at the Messaging Extra-Terrestrial Intelligence (METI) are intending to send more signals into space in the hopes of encountering intelligent life elsewhere in the cosmos. Participating astronomers in this initiative believe that a proactive strategy is more likely to result in successful contact with an extraterrestrial civilization than a pᴀssive one.

In 1977, the Ohio State University Big Ear telescope detected a tremendous radio wave burst that lasted 1 minute and 12 seconds. The radiation’s alphanumeric coding surprised scientists examining it, and it was called the WoW signal.

This is considered the most promising candidate signal since the Search for Extraterrestrial Intelligence (SETI) mission started over six decades ago. An amateur astronomer, Alberto Caballero, recently said that he had identified the signal’s source. For decades, academics have attempted to investigate the signal and its sources in more depth.

The amateur astronomer published his results in the International Journal of Astrobiology earlier this month, but he also has previous achievements to his name. Caballero estimates the number of malevolent extraterrestrial civilizations in one of the papers that has not undergone peer review but is accessible on a pre-print site.

The objective of Caballero’s ᴀssessment is to quantify the number of civilizations that might potentially respond to the communications we transmit.

Caballero, a conflict resolution student at the University of Vigo in Spain, extrapolated certain data from his academic area of study to the subject he is pᴀssionate about in order to arrive at this number. Caballero approximated the number of exoplanets in the Milky Way based on the number of invasions that had occurred on the planet Earth. Vice stated that Italian SETI expert Claudio Maccone placed the number at 15,785 civilizations.

According to Caballero’s estimates, the number of civilizations that may theoretically invade us is four, which is two orders of magnitude less likely than the planet being destroyed by a mᴀssive asteroid.

According to Caballero’s estimation, these four civilizations may be technologically more advanced than human civilization is now, and there is fewer than one civilization capable of interstellar travel that would be required for an invasion.

He warned: “We don’t know the mind of extraterrestrials. An extraterrestrial civilisation may have a brain with a different chemical composition and they might not have our empathy or they might have more psychopathological behaviours. “I found this way to do [the study], which has limitations, because we don’t know the mind of what aliens would be like.”

The conflict resolution student also claimed that as civilizations improve, they become less likely to engage in conflict, and he ᴀssumes in his estimation that an extraterrestrial life force would exhibit the same behavior he has seen on Earth. This may also prove to be untrue. However, Caballero thinks that this will facilitate a worldwide conversation on whether or not we should send out messages.

Reference(s): Research Paper, VICE, NASA