Over the past decade or so, astronomers have speculated about the characteristics of rogue planets in the Milky Way galaxy. These "free-floating" worlds don't orbit stars, but instead roam the ...

IMAGE: An artist’s impression of a free-floating planet. Using observations and archival data from several of NSF’s NOIRLab’s observatories, together with observations from telescopes around the world ...

Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system was touted more than a century ago. But ...

LOS ANGELES - The Milky Way is home to at least 17 billion planets that are similar in size to Earth, a new estimate suggests. That's more than two Earth-size planets for every person on the globe.

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. June’s full moon ...

Carnegie scientists used NASA's James Webb Space Telescope to look at the molten planet orbiting in the Milky Way's thick ...

Add Yahoo as a preferred source to see more of our stories on Google. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far ...