Add Yahoo as a preferred source to see more of our stories on Google. Some 'water worlds' like Jupiter's moon Europa could potentially be habitable for life. NASA/JPL-Caltech/SETI Institute The search ...

A highly stylized rendition of our solar system NASA/JPL If someone asked which planet was closest to Earth, you’d be pretty certain — it’s Venus. We measure distances in the solar system in terms of ...

Astronomers have, for the first time, pinned down both the mass and distance of a planet that drifts through the galaxy without a parent star, turning a once purely theoretical class of worlds into a ...

Astrobiologists disagree about whether advanced life is common or rare in our universe. But new research suggests that one thing is pretty certain – if an Earthlike world with significant water is ...

Astronomers have finally pinned down both the mass and distance of a solitary “rogue” planet, a world that drifts through space without the warmth or light of a parent star. The object, a Saturn-sized ...

More than 10 years after the discovery of the first extrasolar planet, astronomers have now discovered more than 250 of these planets. Until a few years ago, most of the newly discovered exoplanets ...