As astronomers gaze toward nearby planetary systems in search of life, they are focusing their attention on each system’s habitable zone, where heat radiated from the star is just right to keep a ...

The definition of a habitable zone was necessarily simple in the beginning. Any planet at the right distance from its star to allow liquid surface water was considered to be in the habitable zone. But ...

The old adage that it's easier to prove a negative could play a crucial role in characterizing nearby exoplanets that could harbor life. The idea is that looking for earth-like planets is tough enough ...