When astronomers announced Kepler-452b, they were not just adding another distant world to a growing catalog. They were ...

Rings of comets have been discovered around 74 alien star systems, revealing not only the existence of trillions of icy exocomets, but also the source of most of the water in these systems. The ...

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 Penn State-led Habitable Zone Planet Finder (HPF) provides the highest precision measurements to date of infrared signals from nearby stars. Pictured: The HPF instrument during installation in its ...