>> October 16, 2017. Inside the Arctic Circle. EISCAT's 32-meter dish powers up. A 33-minute encoded message propagates toward Luyten's Star, 12.4 light years away.

>> It cannot be recalled. It cannot be canceled. It will arrive. The signals we have already sent are not slowing down. They are not coming back.

>> Liu Cixin's Dark Forest hypothesis, 2008: revealing your position to a sufficiently advanced observer is an existential hazard. The dominant strategy is concealment.

>> We have been broadcasting since 1962. Voyager. Arecibo. Cosmic Call. METI International. Every radar installation. Every TV broadcast. Every WiFi router on Earth.

>> Project Ozma, 1960: Frank Drake listened to the silence. Sixty years later, the silence has not been broken. The signals we have already sent are still in flight.