Add Yahoo as a preferred source to see more of our stories on Google. The Search for Extraterrestrial Intelligence (SETI) focuses on finding technosignatures—potential signs of alien technology. If we ...

Here's what you'll learn when you read this story: Even the most sophisticated radio arrays have not yet detected any signals that could have possibly been beamed through space by aliens. But maybe we ...

The Deep Space Network (DSN) is just the sort of tool aliens could one-day detect, transmitting from Earth. Credit: NASA/JPL What if the first signal ever detected from an alien lifeform wasn't a ...