>Your quote relies on us detecting re-runs of "I Love Lzcwwdrrr", but our telescopes can reliably do spectrographic analysis of faraway stars and planets these

>Your quote relies on us detecting re-runs of "I Love Lzcwwdrrr", but our telescopes can reliably do spectrographic analysis of faraway stars and planets these days. We'd likely be able to detect things like unnaturally high levels of hydrocarbons in otherwise oxygen-full atmospheres, and other industrial by-products. We don't know what "unnatural" levels of CO2 on other planets are. > If Alpha Centauri had a planet with an industrial civilization, we might be able to spot city lights. We do not even remotely have that capability.