Technosignatures are theoretical signs of technologically advanced alien civilizations, but so far, none of those civilizations have phoned home. Researchers from the Search for ExtraTerrestrial ...

Here’s what you’ll learn when you read this story: Technosignatures are theoretical signs of technologically advanced alien civilizations, but so far, none of those civilizations have phoned home.

For most people, the idea of alien contact has been shaped less by astronomy than by cinema. Films have taught us to expect intention: visitors who arrive either with open hands, as in E.T., or with ...