What can Earth’s technosignatures—the potential signs of intelligence beyond Earth—teach us about finding technosignatures throughout the cosmos? Are we looking for the right technosignatures or do we need to refine our search methods or criterion? This is what a recent study published in The Astronomical Journal hopes to address as a team of researchers led by the SETI Institute essentially flipped the script to evaluate if current methods for detecting technosignatures are sufficient or could be modified going forward.
For the study, the researchers used a series of models to simulate the efficiency and distance that Earth’s technology in 2024 could be detected by an extraterrestrial civilization. This study comes as telescope instruments continue to advance, including identifying atmospheric compositions of exoplanets. Therefore, the goal of this work is to enhance this to potentially identify new methods in detecting technosignatures by using Earth as a control group as opposed to literally every other known world in the universe. In the end, the researchers found that extraterrestrial civilizations could potentially detect Earth technology as far as 12,000 light-years away, noting that the closer they travel to Earth, the more modern-day technology they would detect.
“One of the most satisfying aspects of this work was getting to use SETI as a cosmic mirror: what does Earth look like to the rest of the galaxy? And how would our current impacts on our planet be perceived,” said Dr. Sofia Sheikh, who is a postdoctoral researcher at the SETI Institute and lead author of the study. “While of course we cannot know the answer, this work allowed us to extrapolate and imagine what we might assume if we ever discover a planet, with, say, high concentrations of pollutants in its atmosphere.”
