SETI at 50

摘要

The search for extraterrestrial intelligence (SETI), a research discipline that celebrates the 50th anniversary of its inaugural publication this week (see page 345), has always sat at the edge of mainstream astronomy. This is partly because, no matter how scientifically rigorous its practitioners try to be, SETI can't escape an association with UFO believers and other such crackpots. But it is also because SETI is arguably not a falsifiable experiment.rnRegardless of how exhaustively the Galaxy is searched, the null result of radio silence doesn't rule out the existence of alien civilizations. It means only that those civilizations might not be using radio to communicate. Indeed, SETI is marked by a hope, bordering on faith, that not only are there civilizations broadcasting out there, but that they are somehow intent on beaming their signals at Earth.