SETI Or METI? Signals Or Spheres?

METI (Messaging to Extraterrestrial Intelligence) isn’t a new idea, but is getting increasing backing from sections of the SETI community. Centauri Dreams wonders whether broadcasting the interstellar equivalent of a cheery “hey, you guys!” is a wise move – shouldn’t there at least be some reasoned debate before calling open house? Meanwhile, Sentient Developments discusses a new paper that proposes we shouldn’t be looking for signals but for artificial objects (like Dyson Spheres) around stars as indicators of the presence of alien civilisations.