⁠ There are two ways to look for extraterrestrial life. We’ve been focusing on only one, Adam Frank writes. ⁠ ⁠ On Earth, and presumably beyond, life exists on a spectrum of forms and capacities. But for the purposes of tracking it down in the cosmos, it can be lumped into two somewhat crude categories: “dumb life” (things such as microbes and plants that can proliferate across a planet) and “smart life” (creatures like us that build planet-spanning technologies). To look for the former, astronomers focus on finding biosignatures, such as the presence of oxygen and methane in the atmosphere; to look for the latter, they might search for technosignatures— the presence of complex industrial chemicals in the atmosphere that would indicate that a technologically capable species like us inhabits that distant world.⁠ ⁠ “So far, in the search for extraterrestrial life, dumb life has won out,” Frank continues. “The allure of biosignatures is clear. Many astronomers start out assuming that biosignatures will be more prevalent than technosignatures. After all, you can’t have a civilization-building species evolve on a planet before life does ... Unlike biosignatures, technosignatures move and endure ... Technosignatures could also be prolific. A single civilization and its technosphere could produce millions or even billions of individual objects that each could create detectable technosignatures.”⁠ ⁠ “So far, scientists have designed their life-detection tools to target either smart or dumb life, but in the wake of discovering exoplanets, the same kinds of telescopes and the same kinds of detectors attached to those telescopes can now be deployed for finding both kinds of life,” Frank continues at the link in our bio. “After thousands of years of arguing over the question of life in the universe, we are finally capable of searching for answers. Finding any kind of life—dumb or smart—would constitute a fundamental reframing of our place in the cosmos. Let’s look for all of it.”