Talking to Extraterrestrials
For over fifty years, astronomers have pointed their telescopes to the sky, looking for signals from advanced civilizations—a project called SETI, the search for extraterrestrial civilizations. So far, they’ve found nothing. But what if there *are* other civilizations out there, but they’re doing exactly what we are doing—simply listening, and not transmitting? I advocate a new approach to making contact called Active SETI, where we don’t simply listen for signals from extraterrestrials, but instead we send powerful, intentional radio signals to other star systems, in the hope of receiving a reply.