As the United States prepares to celebrate its 250th anniversary, the history of the solar system tells its own story of ...

Two faint objects hiding in archival infrared sky maps now sit at the center of a growing scientific argument about whether a ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...

With the same data but a different statistical analysis, researchers have spotted two additional planets in a system that was already thought to host seven of them ...