This is where artificial intelligence comes in. Volunteers on the Zooniverse citizen science platform help categorize known RFI patterns, training a machine learning system to conduct future searches faster and more efficiently. “The machine learning model we’re using is a convolutional neural network,” says Li, “which relies on iterative calculus to recognize similar patterns across images. This technology is similar to that used in self-driving cars: Just as we want a car to distinguish red from green lights, we want our model to reliably identify one type of radio frequency interference from another. We’re training the model to identify distinct RFI types because if its understanding of RFI is too broad, we risk discarding potential extraterrestrial signals. Thanks to the patterns labeled by our volunteers, we’re training the network to identify these specific RFI types.”
Caution is needed when using AI for SETI research. AI’s drive to maximize metrics like speed and efficiency can lead to problems. “AI might quickly ‘solve’ the question of whether a SETI search found ET by simply answering ‘no’ each time,” Li explains, “and such an answer would go unnoticed. Conversely, if AI leans too far toward identifying everything as ET-related, we face issues with model accuracy.” This is why the project uses AI to assist with specific tasks rather than making decisions about potential ET signals on its own.
Although AI research is a complex and growing field, Li emphasizes that it is accessible to everyone. “When I began this project in 2023, I had no prior experience with AI and only three years of basic Python programming under my belt. Starting out, I felt intimidated, and the entire endeavor seemed overwhelming. But today, I no longer feel that way. I am living proof that working with AI isn’t reserved for elite programmers; anyone can join in thanks to the plethora of free tools and resources available online.”
The potential for AI in SETI research also raises an intriguing possibility: If there are other technologically advanced civilizations out there using AI as a tool for exploration, one artificial intelligence could someday detect another. “One of the things I love about SETI,” says Li, “is how our ideas about contact evolve with humanity’s own experiences. The Drake Equation, a formula for estimating the probability of contact, has changed with us, sometimes factoring in civilization-ending risks like nuclear war or climate change. I imagine that some may already be advocating for an ‘AI-takeover’ variable!”