Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

The curious minds at What If discover what happens if a new planet appears in our solar system, revealing gravitational ...

New simulations suggest Jupiter holds far more water than once thought, reshaping ideas about how the largest planet formed.

NASA’s newly launched IMAP mission is set to tell us more about the boundary between our Solar System and interstellar space ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...

Planet Y is the latest in a series of hypothetical solar system planets that scientists have proposed in recent years, all with slightly different characteristics but collectively believed to be ...