Asking questions


By William Alba 

William Alba is Associate Teaching Professor in Chemistry and Assistant Dean for Diversity in the Mellon College of Science at Carnegie Mellon University, where he directs two academic programs. He serves on the Advisory Council of METI International, the Advisory Board of Arch Mission Foundation, and the Board of Directors of the Society for Social and Conceptual Issues in Astrobiology.

Earlier this year, astronomers with the Breakthrough Listen project detected a narrow-band radio signal (BLC1) from the direction of Proxima Centauri. Scientists continue to verify and analyze data to determine whether BLC1 might be an intentional message from an extraterrestrial civilization.

Suppose careful examination of evidence suggests BLC1 is an interstellar message. Because Proxima Centauri is only four-and-a-quarter light years away, if we begin transmitting a response, we could receive replies in well under a decade. Most people living today would witness the first exchange of information between aliens and ourselves. 

If some alien intelligence is sending messages to us here on Earth, and if we decide to respond, what types of messages should we send? Independent of BLC1, we should be prepared to reply whenever we receive a verified extraterrestrial message. The same question also holds if we decide to send messages ourselves to other stars: what should our messages include?

To address this, it's worth thinking about how we ourselves behave when we meet fellow humans — whether online, or in person while taking appropriate precautions in this post-COVID-19 world.


Imagine you arrive to a party. Not seeing anyone familiar, you approach the nearest person. This stranger locks eyes with you and begins to drone numbers: 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9 ...

What would you think of such a person? How long would you endure this, before gesturing towards the drinks and edging away in that direction?

Pouring yourself a cold one, you remark to someone standing nearby, "There sure are some interesting people at this party, aren’t there?" You are relieved to hear the person respond in words: Let me tell you about interesting. I was on the home page of Wikipedia... Your relief subsides when this person continues to recite this information. Verbatim.

You look around and wave to a group of people across the room. You introduce yourself and ask for their names. One person replies and continues to relate a funny incident that happened to them today. Just as you start to get comfortable, you realize this person won’t stop talking.

Paying attention to the drone of voices at this party, you realize that everyone is talking only about themselves: what they know, what happened to them, where they are from. They fail to ask questions about you or anyone else. Heading for the exit, you leave behind this gathering of automatons and narcissists.


We humans are social beings. When we meet each other, we ask questions. And this is not merely a social convention — asking questions reflects both curiosity and humility: we seek to learn, and we admit the extent of our ignorance. Children ask questions frequently. At any age, whenever we want to understand and express ourselves in a new language, we learn how to ask questions. Furthermore, when we find ourselves in an unfamiliar place where we do not know the local culture, we ask questions.

In contrast, in our previous messages for extraterrestrial intelligence (METI), we have behaved more like the bores and boors at our imagined party. We talk almost entirely about ourselves. On the Voyager Record, only six of the 55 spoken greetings ask questions, briefly inquiring about the condition of the alien recipients. Of our radio transmissions, only Cosmic Call asks the extraterrestrial receivers to share information about themselves.

We already know how we could ask questions of aliens, even in the absence of a shared language. Well before the Cosmic Call signals in 1999 and 2003, and before Voyager 1 and 2 spacecraft were launched in 1977, scholars theorized how we would ask questions of extraterrestrial intelligences. In 1960, Hans Freudenthal described LINCOS, a "cosmic language" that introduced questions at an early stage. Establishing the interrogative allows LINCOS to distinguish between the truth of a mathematical expression (true/false) and its desirability (good/bad). In 1963, Lancelot Hogben proposed Astraglossa, where he also emphasized establishing the interrogative. Both of these METI scholars at the dawn of the Space Age recognized the importance of asking questions. LINCOS proposes a detailed syntax to express questions, providing a starting point for contemporary practitioners.

Our identities and intelligences as human beings depend upon asking questions. Therefore, our METI practice should include questions, to better reflect our own nature.


I advocated this perspective two weeks ago at the Society for Social and Conceptual Issues in Astrobiology (SSoCIA) biennial conference, where Doug Estes independently raised similar issues. In my presentation and during the subsequent discussion, I admitted that question-asking can serve different intended functions, that asking questions relies upon establishing a broader context, and that questions can be misconstrued. For example, being humble enough to ask questions could be interpreted as being vulnerable or weak; conversely, being bold enough to ask them could be apprehended as being dominant or even hostile. There is potential to be misunderstood when asking questions — but this is possible with any act of communication, even between humans. All the more reason to take care when we conduct METI.

If we do actively practice METI and agree that question-asking is important, what questions should we ask aliens? One approach would be to notice the vast array of questions we already ask of each other: enduring questions in canonical texts; common questions from children; research questions that identify the frontiers of our knowledge; …

METI practitioners should also actively seek a diversity of opinions, in order to determine whether, how, and what to communicate. We otherwise run the danger of inaccurately representing our planet. An example of the importance of diverse perspectives: every question on the Voyager Record was spoken in a language from Asia or Africa. This iconic artifact would otherwise lack any trace of asking questions, which is a fundamental characteristic of being human. Opinions of experts and the general public can complement each other. The Earth Tapestry project I developed invites website visitors to rank terrestrial locations according to eight different criteria. A snapshot of this data is now archived on the Moon, as part of the Arch Mission Foundation library carried by Beresheet, which made a hard landing in April 2019.

Yet another method would be to notice what we ask when we find ourselves in comparable situations involving “first contact.” These would include the questions everyone learns when acquiring a new language, when acclimating to unfamiliar circumstances, and yes, even when meeting people at a party for the first time. 

My hope is that reframing METI in terms of asking questions will bring into focus — both for practitioners and the public — why, whether, and how we should send messages beyond our solar system.