Humans should look to planetary alignments outside of the solar system when searching for signatures of extraterrestrial communications, scientists say. The nascent search for radio transmissions from ...

You’ve traveled thousands of light-years through interstellar star systems. And now you’re stranded on a planet you know nothing about. As long as you’ve got oxygen, water and food aboard your ...

A team of astronomers claims to have sniffed out a “biosignature” in the atmosphere of a distant planet called K2-18b. But not everyone agrees that it signals life. An illustration shows what ...

Scientists have detected a hidden alien planet by examining the orbits of the known worlds in the star system, known as Kepler-139. The newfound exoplanet, called Kepler-139f, is a gigantic world ...