An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course. When ...

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 ...

There’s a bit of a paradox about our galaxy: it’s both jam-packed with stars and cavernously empty. The Milky Way is crowded in the sense that it holds hundreds of billions of stars, as well as ...