A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth ...

ZURICH, Switzerland — In our quest to answer whether we’re alone in the universe, astronomers are preparing for a major advancement: new space telescopes capable of scanning distant worlds for signs ...

A low-density, puffy planet orbiting relatively far from a young star in a nearly perpendicular orbit. What's going on?

Space scientists look back on 30 years of exoplanet discoveries — from rows of massive ‘super-Earths‘ to worlds with ...

From lava worlds to gas giants, NASA says the variety of these worlds is staggering—and that signs of a further 8,000 distant ...