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 ...

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

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 ...

3I/ATLAS, earlier known as A11pI3Z, is only the third interstellar visitor to be discovered passing through our corner of the galaxy. By Kenneth Chang For only the third time, astronomers have found ...