Recent observations suggest that 'runaway' black holes are tumbling through the cosmos. Building on decades of theory, the discovery adds a remarkable new chapter to the story of the universe.

Supermassive black holes rarely travel alone. Most large galaxies hide one at the center, and when galaxies collide, the two ...

Astronomers have observed a planetary system that challenges current planet formation theories, with a rocky planet that formed beyond the orbits of its gaseous neighbors, possibly after much of the ...

Since the 1990s, astronomers have found a handful of other dwarf planets in the belt, such as Eris and Sedna, along with ...