There could be a ninth planet in our Solar System after all - and no, it's not Pluto. Instead, it's the theoretical Planet X, also called Planet Nine, a wide-orbit planet that would circle the Sun ...

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 ...

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. NEW YORK (AP) — A new Tatooine-like planet ...

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today." When you purchase through links on our site, we may earn an affiliate ...

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 ...