Add Yahoo as a preferred source to see more of our stories on Google. An artist's concept shows what K2-18b might look like. Thought to be covered entirely in liquid water with a hydrogen-rich ...

Just because Pluto was ruled out as a planet in 2006 doesn’t mean our solar system only has eight planets. The search for Planet Nine is far from over as scientists continue to uncover clues ...

A team of astronomers have detected what they call the most promising signs to date of a possible biosignature, or signs of past or present life linked to biological activity, on an exoplanet named K2 ...

(CNN) — A tiny sign revealed in April seemed like it might change the universe as we know it. Astronomers had detected just a hint, a glimmer of two molecules swirling in the atmosphere of a distant ...

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