News in Brief Astronomy

We probably won’t hear from aliens. But by the time we do, they’ll be dead.

A new Drake Equation calculation suggests ghost signals haunt parts of the Milky Way

animation of signals from alien civilizations

CAN YOU HEAR ME NOW?  Electromagnetic signals (blue circles) from alien civilizations will continue traveling through the Milky Way even after the aliens are gone. The appearance of a doughnut hole represents when a civilization dies out.

Geoff Marcy

By Lisa Grossman

- More than 2 years ago

If signals from an alien civilization ever reach Earth, odds are the aliens will already be dead.