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If Earth’s astronomical observatories were to pick up a signal from outer space, it would require an all-hands-on-deck effort to untangle and decipher the extraterrestrial message.
An art project from the SETI Institute, a nonprofit in Mountain View, California, devoted to searching for life beyond Earth, simulated that scenario over a year ago before a father-daughter team of citizen scientists recently deciphered the message. Its meaning, however, remains a mystery.
After the ExoMars Trace Gas Orbiter, a European Space Agency spacecraft orbiting Mars, beamed a signal containing an alien-like message in May 2023, three observatories on Earth picked it up and released the raw data on the internet, giving citizen scientists across the globe a chance to decipher the transmission.
Ken Chaffin and daughter Keli, who worked on decoding the message for nearly a year, uncovered the answer in June, the European Space Agency announced on October 22. Doing so required thousands of hours experimenting with various ideas and running mathematical simulations on a computer, the Chaffins told CNN.
In what appears to be clusters of white pixels on a black background, the visualized message is of five configurations that represent amino acids, the building blocks of life. The message is not static but is in motion and only displays the arrangement for about one-tenth of a second. The project’s designers confirmed that amino acids are the intended message, but they are leaving the interpretation open.
Now, citizen scientists are grappling with the meaning behind the cryptic cosmic puzzle. So far, the community engaged in the project has not been able to determine and agree on what the amino acids represent.
Decoding the cosmic puzzle
Daniela de Paulis, an artist in residence at the SETI Institute and recipient of the Baruch Blumberg Visiting Fellowship in Astrobiology at the Green Bank Observatory in West Virginia, designed the project, called “A Sign in Space,” alongside a small team of international scientists and artists who explored what a signal from an extraterrestrial might look like.
The signal was sent from Mars to Earth — traveling 16 minutes through space before being picked up by the Allen Telescope Array in Northern California, the Robert C. Byrd Green Bank Telescope and the Medicina Radio Astronomical Station near Bologna, Italy. Then citizen scientists, communicating through a global Discord chat, extracted the raw data that was tangled with other data from the Mars spacecraft. It took around 10 days to extract and visualize the data, but deciphering what the message was took even more persistence.
When Ken Chaffin came across the original image from the scrambled raw data, which the Discord community of citizen scientists referred to as the “starmap,” he said he suspected a cellular automata algorithm produced it. Cellular automata are grids of units that are mathematically coded to move or follow certain sets of rules. “I knew I had the skills to decode the message,” he said in an email, explaining he has decades of amateur experience working with cellular automata.
By running the cellular automata simulations on the “starmap,” the Chaffins were eventually able to generate the image of the amino acids.
“I had no idea what the message would show or say,” he added. “I suspected that it might have something to do with life.” When the image of the clusters revealed itself, Chaffin said he immediately recognized them to be amino acids from school chemistry classes.
Keli Chaffin, his adult daughter, initially had no plans to join her dad in the immersive effort, but she said she quickly became mesmerized by the vastness of the project.
“The original image that looks like a starmap has always given me the appearance of biological lifeforms,” she said in an email. “(A) lot of members have seen a mouse, a starfish or an elephant.
“Maybe that is just us as humans looking for the recognizable within random dots, a Rorschach test of sorts.”
The project’s goal was to keep the simulation as close as possible to how it might occur in real life, de Paulis said, so the project developers did not give any help, including confirmation or denial, until receiving the solution from the Chaffins.
“The idea is that if we ever received a message from an alien civilization, we would not have feedback. So, we will have to come up with the meaning ourselves,” said de Paulis, who is also a licensed radio operator. “There were basically thousands of interpretations, because … everybody was really moving in the dark. They didn’t know where to go. They just have this image of a ‘starmap’ that everyone interpreted in many possible ways.”
The signal is a representation of what it would be like to receive an extraterrestrial message under ideal circumstances, as it came from relatively nearby Mars and was thus a stronger transmission than one that might come from deep space, de Paulis said. Multiple telescopes picked up the signal, whereas only one might detect an actual extraterrestrial, she added.
The project team intentionally created a complex message, with some team members predicting it could take weeks or even years to be decoded. “Someone said, ‘Maybe they’re never going to interpret it,’” de Paulis said. “So we had no idea how long it would take. We really took this huge risk.”
Now that the message has been unlocked, the next step is to figure out what it means and why another civilization would send it, she said.
Interpreting an extraterrestrial message
The designers behind the project don’t plan on confirming or denying any possible interpretations soon, but they are asking the public to send in ideas while de Paulis works on a book that will encapsulate the project and interpretations of the message.
On a global scale, it’s difficult to agree on a meaning with so many people from different backgrounds and cultures involved, she added. “The chances are that in this extreme scenario, when we have to give a meaning to a message from an alien civilization, we might never be able to really agree on an exact meaning.”
The father-daughter team has tossed around hundreds of possible interpretations, Ken Chaffin said. If the moving message begins with the amino acid configuration, then it appears as if the five clusters deconstruct and move throughout space. If the message starts with the scrambled “starmap” and ends on the amino acids coming together, it could represent various compounds such as hydrogen, carbon, nitrogen and oxygen being transported across space and then assembled into life, he said.
A representation of panspermia, the theory that life exists throughout the universe and is distributed, was one of his favorite interpretations, he said.
“In the end it is up to each viewer to interpret it just like the Rorschach Test, we may never know what the ‘aliens’ were trying to tell us,” Keli Chaffin said. “It might just be them saying ‘Hello!’
“I think for me the most exciting part was having the opportunity to work with my father on such a once in a lifetime project,” she added. “We don’t give up on a project even if it is deemed near impossible.”
