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 ...

Astronomers have long been on the hunt for "Planet Nine," a hypothetical planet that lies within our solar system just beyond Neptune. Scientific evidence has alternately pointed to and against the ...

For years, astronomers have searched for Planet Nine, a hypothetical world thought to lurk far beyond Neptune. Its existence ...

Planet 9 sits at the edge of scientific imagination, promising either an epic expansion of the Solar System or a lesson in how easily patterns can mislead us. As new data arrive and old assumptions ...

After studying thousands of computer simulations of the solar system, researchers at Rice University and the Planetary Science Institute think there’s a 40% chance an elusive “Planet Nine” or “Planet ...

A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth than the hypothetical Planet X, which astronomers have been hunting for ...

(CNN) — 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 ...