Should We Develop an ET Encounter Manual?

Avi Loeb
4 min readJan 6, 2023

In the event of an extraterrestrial (ET) encounter, what should we do? Meeting a stranger in your backyard is alarming and requires a prompt response. The measured response of humanity would be to learn more about the ET visitor, because the context might be surprising.

The experience will definitely bring new insights to the perception of our cosmic neighborhood and our future aspirations for space. Slowly, the groundbreaking realization will sink in: rather than watch the stars from a distance, something from there came to visit us here.

It would be prudent to collect passively as much information as possible about the visitor before engaging with it. We will need to figure out its intent, get a sense of the information it is seeking and decode its gestures or signals.

If the visitor is just defunct space trash, like our current spacecraft will be in a billion years, we could learn where it came from by studying it in a laboratory. This is what the Galileo Project plans to do with the fragments of the first interstellar meteor from 2014 after a dedicated expedition will retrieve them from the ocean floor near Papua New Guinea in 2023.

But the visitor may possess artificial intelligence (AI), in which case the interpretation task will be best handled by psychologists, linguists, philosophers, code breakers and AI scientists, who are trained to interpret intelligent signals. The most suitable set of experts will depend on the nature and behavior of the visitor.

Traditional bureaucrats or scholars would always argue that we need to establish a large committee ahead of any encounter that will compose a thick “ET Encounter” manual, outlining different scenarios and how to act in each of them. This approach is misguided because such a committee has no empirical basis to ground its expectations. The imagination of the committee members may not capture the true nature of the real ET encounter, because we had no such experience in the past. Any encounter is a dialogue; we need to collect data on the visitor before we can contemplate what to do in response. For this brand new and consequential experience, the committee’s compromised consensus may not be the wisest move, since it is often said that “a camel is a horse designed by a committee.”

Speaking about horses, it is important to make sure that we are not dealing with a Trojan Horse that masquerades its true intention. It is unlikely that we will encounter biological creatures because the required journey through interstellar space is long — taking millions to billions of years, and hazardous — as a result of the bombardment by energetic particles, dust and high-energy radiation. Instead, we are likely to confront technological equipment with AI, and we better employ our best AI algorithms to interpret it. Paraphrasing the aphorism about committees: “a self-driving car is a private chauffeur designed by AI.”

I am not worried about the threat from an ET visitor. Our modern technologies were developed merely over the past century, a tiny fraction of the billions of years by which ET technological civilizations near older stars predated us. They had plenty of time to decimate life on Earth long before we arrived at the scene. Instead, the encounter could be a great learning opportunity for us, through which we can get a glimpse at our technological future. This would be a teaching moment for appreciating how much we need to learn in order to enter the club of interstellar civilizations.

During a television interview on this matter last night, the host Lisa Kennedy Montgomery asked me: “Would you like to be the guy in charge of deciding what to do in case of an arrival?”, to which I replied: “I would be delighted to be involved … but if we ever need to communicate with an extraterrestrial gadget, I would rather let a woman handle this delicate task, because women have better communication skills.”


Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He chairs the advisory board for the Breakthrough Starshot project, and is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. His new book, titled “Interstellar”, is scheduled for publication in August 2023.



Avi Loeb

Avi Loeb is the Baird Professor of Science and Institute director at Harvard University and the bestselling author of “Extraterrestrial” and "Interstellar".