However, what constitutes a planet in particular is a question that may seem very simple but has been escalating in complexity as scientists discover new planets that defy the classical definition.

A young alien planet, wandering alone in the galaxy, has surprised astronomers by gobbling up gas and dust at a rate faster than they've ever seen before. Throughout the Milky Way, there are ...

Add Yahoo as a preferred source to see more of our stories on Google. (AFP/Getty) Scientists have spotted a “rogue” planet floating on its own through space. Most of the planets we know are found ...

Scientists now have direct evidence that a planet — not just failed stars — can rove the galaxy after a violent expulsion from its orbit. Credit: NASA / JPL-Caltech / R. Hurt illustration Astronomers ...

Astronomers have detected a rogue planet with a mass equivalent to that of Saturn, and by taking observations from both the ground and space, they have also been able to measure its size and distance ...

While most planets that we are familiar with stick relatively close to their host star in a predictable orbit, some planets seem to have been knocked out of their orbits, floating through space free ...

Astronomers have uncovered a runaway feeding frenzy in a rogue planet drifting freely through space, devouring six billion tonnes of gas and dust every second. Located 620 light-years away in the ...

Free-floating planets, or as they are more commonly known, rogue planets, wander interstellar space completely alone. Saying there might be a lot of them is a bit of an understatement. Recent ...

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. About 620 light-years from Earth, a gigantic rogue proto-planet is ...