Alien hunters are getting closer to detecting extraterrestrial communications, thanks to a new technique that could capture radio signals sent between planets.
At a glance:
- Astronomers have developed a method to detect narrowband radio signals that might be exchanged between alien planets, even if not intended for deep space.
- The technique was tested on the TRAPPIST-1 star system, home to seven Earth-sized exoplanets, three of which orbit within the habitable zone.
- While no alien signals were detected, the method proved effective and could be applied to other star systems in future searches for extraterrestrial life.
In an exciting breakthrough for the search for extraterrestrial life, scientists have developed a new technique to listen for radio signals that alien civilizations might be sending between planets. This method, designed to capture narrowband radio signals, could detect transmissions similar to those humans use to communicate with spacecraft.
The method was put to the test in the TRAPPIST-1 system, located just 41 light years away from Earth. This star system is notable for its seven rocky, Earth-sized planets, three of which are in the “habitable zone” where conditions might support liquid water and life. Although no alien communications were picked up during the experiment, researchers demonstrated that their approach works and could be applied to other planetary systems in the search for extraterrestrial technosignatures.
According to Nick Tusay, an astronomer at Penn State University and lead author of the study, the team focused on picking up radio signals with much smaller bandwidths than those typically assumed in such searches. These signals could be used by alien civilizations to communicate with spacecraft or probes within their own systems, much like we do on Earth. “Most searches assume a powerful signal, like a beacon intended to reach distant planets,” Tusay explained, but this new method is designed to detect weaker signals that may not have been intended to travel beyond a single planetary system.
The team used the Allan Telescope Array, a series of radio telescopes, to scan TRAPPIST-1 for 28 hours, during which seven potential “planet-planet occultations” occurred. These occultations are moments when one planet passes in front of another, offering a chance to catch radio signals spilling over from one planet to another.
While none of the 2,200 candidate signals were confirmed as extraterrestrial communications, the results are still significant. The researchers believe their method could be expanded to scan other star systems, improving the odds of detecting extraterrestrial civilizations if they exist.
TRAPPIST-1’s proximity and detailed orbital information made it an ideal testing ground, but as Tusay noted, “The methods and algorithms that we developed for this project can eventually be applied to other star systems.” This opens up new possibilities for the future of alien signal detection, bringing us one step closer to answering the age-old question: are we alone in the universe?
