Exoplanets like Earth have been discovered but not all Earth-like planets are equal when it comes to alien life.

WASHINGTON — An Earth-sized planet in its star's habitable zone has been discovered in data from NASA’s Kepler space telescope. NASA says the newly found exoplanet is the closest to Earth in size and ...

In a major first, scientists have detected water vapor and possibly even liquid water clouds that rain in the atmosphere of a strange exoplanet that lies in the habitable zone of its host star about ...

Alien solar systems that are home to so-called "hot Jupiters" — gas giants circling sizzlingly close to their stars — are unlikely homes for Earth-like planets, researchers say. Hot Jupiters get their ...

The Search for Extraterrestrial Intelligence (SETI) focuses on finding technosignatures—potential signs of alien technology. If we look carefully, we might have a chance at detecting their ...