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 ...

For centuries, humans have gazed at the stars, trying to understand what lies beyond the familiar planets we know. From Mercury’s blazing orbit near the Sun to Neptune’s icy edge, our Solar System has ...

A Jupiter-size exoplanet orbiting a dead star baffled astronomers. But the planet named WD 1856 b could preview the fate of our own solar system when the sun dies.

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 ...