For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, Pluto was officially reclassified as a dwarf planet by the International ...

For years, astronomers have been searching for a ninth planet in our solar system (after giving Pluto the old heave-ho and demoting it to a dwarf planet) and now researchers say they've found a ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. An object has been discovered orbiting the sun far beyond ...

Stars passing close to the sun could cause planets to collide, including with Earth, or even be ejected as rogue planets, new simulations show. By Katherine Kornei If our species manages to hang on ...