“‘Technosignatures refer to any evidence of technology that could be remotely detectable, specifically through the tools of astronomy,’ explained Jacob Haqq-Misra, an astrobiologist and senior research investigator at Blue Marble Space Institute of Science, in an email interview with The Debrief. ‘Radio signals are one example of a technosignature but not the only one. Other examples are city lights, surface modifications (cities and large-scale deployment of solar panels), changes in the atmosphere (greenhouse gases like CO2 as well as industrial byproducts like CFCs and NO2), free-floating spacecraft, megastructures (i.e, Dyson spheres/swarms), and other possibilities.’
Hunting for otherworldly technology is no longer science fiction. In 2018, NASA hosted a workshop on the subject of technosignatures, and a report was developed concluding that the study of possible alien technology was an important step for future NASA missions. Today, astronomers, astrobiologists, and other scientists gather online to talk about their work and progress on the subject. The idea of systematically searching for signs of industrial or space-faring civilizations was once laughed out of the room, but now the topic is gaining rock-star cachet and serious popularity within the field of astrobiology.”
-MJ Banias, “Meet The Scientists Hunting for Alien Technology Through ‘Technosignatures’.” The Debrief. December 28, 2020.