The implications of an encounter with extraterrestrial life is a staple of popular culture. All too often, the conflict concerns a violent clash with a more technologically advanced civilization. But it’s entirely possible that the initial challenge might not concern death rays and flying saucers at all.

How would humankind initiate meaningful communication with beings of entirely separate linguistic and biological development? Even that question assumes an encounter with biological beings — not machines or some otherwise distinct form of sentience. And the multitude of possibilities is fully imagined by Brian S. McConnell in his book, The Alien Communication Handbook.

Far from a flight of fancy one might find in the latest Roland Emmerich movie, The Alien Communication Handbook takes the notion of humanity’s first contact with aliens seriously from a linguistic and scientific view.

McConnell approaches the subject with analytical incisiveness. For instance, chapter two examines the prerequisites, incentives, and communicational limits in such a situation. What are the basic prerequisites for a civilization to achieve the capability of communication across vast swaths of space? McConnell suggests that the base requirements are an understanding of electromagnetic radiation, the fundamentals of information theory, and astronomy. Likewise, institutions searching for extraterrestrial life are looking for basic similarities with human civilizational progress, including technological and scientific literacy, a mastery of symbolic communication, and a theory of mind.

“With that in mind, we can anticipate some of the goals in designing a signal that can both be detected across interstellar distances and that can be understood at least partially by a recipient who has had no prior contact with the sender,” McConnell writes.

So let’s say one of the multiple survey operations designed to intercept signals from space picks up evidence of an alien civilization. McConnell breaks down what he imagines as the timeline of events following such a historic discovery, which he acknowledges could change dramatically depending on the nature of the signal and the information extracted from it. The process of simply understanding the modulation scheme and decoding the message into something comprehensible would itself be a major undertaking by the scientific community.

Assuming a successful completion, the next challenge would be to determine whether to respond, which itself could be a matter of intense international debate.

“There are many people in the SETI (search for extraterrestrial intelligence) community who harbor strong reservations about actively messaging other civilizations,” writes McConnell. “How this debate would play out will probably depend a lot on the information content of the transmission and our ability to understand it.”

Assuming all involved decision makers agree to respond and sign off on the response content, get ready for a long wait. It could take years for a response to reach the original sender. But by making inferences about the nature of the response, the civilization could theoretically adjust their messaging procedures to allow for clearer communication.

This sequence of events — and the time needed for it to unfold — is highly dependent on the delivery mechanism. Possibilities outlined by McConnell include electromagnetic radiation, inscribed matter (similar to the golden record carried by Voyager 1 bearing information from Earth), gravitational radiation, and perhaps methods of communication we currently do not comprehend fully.

“Many possibilities have been suggested, but because they typically involve physics that we do not yet understand, it is not possible to design instruments to detect them,” McConnell writes.

From there, The Alien Communication Handbook launches into highly specific analyses of the systems an alien civilization might employ and the content they might include to initiate communication. For example, if an alien civilization is advanced enough to communicate across mind-boggling distances, it may be a fair assumption that they’ve also developed sophisticated algorithmic communication systems.

“An algorithmic communication system is attractive because the amount of information that can be transmitted across an interstellar link is finite and possibly quite small relative to the amount of information the sender might want to share,” McConnell writes. “If the sender can compress data using an algorithm and includes an algorithm that can be used to decompress it on the receiving end, the sender can increase the effective carrying capacity of the link manyfold.”

Imagining the types of information we might receive from a well-compressed message is both thrilling and bewildering. For instance, in the chapter about images that might potentially be sent to us by alien civilizations, McConnell acknowledges that both parties technically understanding photography might be a reasonable assumption. But assuming that the communicating aliens use vision as a primary sense might not be.

“It is possible to imagine a species whose primary sense is auditory but has worked out how to map electromagnetic radiation into a form they can understand,” McConnell writes. “This is similar to how we developed ultrasound technology that enables us to transform ultrasonic echoes into images we can understand.”

A similar level of rigor is applied to three-dimensional images and models, videos and simulations, sound, and other communication methods. It speaks to the sheer breadth of possibility in imagining what contact with an alien civilization might look like. And that’s why McConnell argues that the imaginative work of such an undertaking should be open to a variety of participants.

“It is possible that some of the most important contributions will come from diverse people who are not affiliated with SETI and who may approach these problems from very different perspectives,” he writes.

It’s worth noting that while the book doesn’t shy away from highly technical analysis, it’s still written with enough clarity and summarization to be comprehensible for the layman. No doubt, detailed discussions of computer languages and encoding methods can be dizzying for some readers. But anyone with an interest in the subject — and let’s be honest, contact with alien civilizations is an inherently interesting subject — should find the book a valuable and informative experience.

After all, what’s more exciting than the potential discovery that we are not alone in the universe? The implications of such an encounter could prove more important for human civilization than any other in recorded history. What could a vastly more advanced civilization, assuming a degree of benevolence, teach us about space travel? What do art and culture from a civilization untouched by human influence look like, assuming they exist in a comprehensible form to us at all? What might we learn about the nature of life in the universe? Perhaps most intriguingly, what might we learn about ourselves?

“Just as we are systematically searching for planets outside our solar system and have already cataloged thousands of them, it’s not hard to imagine an ET civilization conducting similar surveys of the worlds they can see, except at higher resolution that what we are capable of today,” McConnell writes.

McConnell ends the book on that enticing note, offering up the possibility that any advanced civilization we might encounter may have been aware of us since the dawn of humanity. And who knows? Perhaps they’ve been documenting and analyzing our development as a species more thoroughly than we have ourselves. After all, when it comes to mysteries hidden within the endless expanse of the universe, the sky’s not the limit — it’s just the beginning.