A young star called V1298 Tau is giving astronomers a front-row seat to the birth of the galaxy’s most common planets. Four massive but extremely low-density worlds orbiting the star appear to be ...

For centuries our solar system was the only planetary system known to humans. We had no proof other worlds existed beyond those in our own cosmic backyard, and we imagined that if other planetary ...

Astronomers have spotted a lonely world roughly the size and mass of Saturn, drifting through the Milky Way without a star to orbit. The discovery turns a once theoretical curiosity into a concrete ...