Far beyond Neptune, something heavy appears to be tugging on the outer solar system, bending the paths of distant icy worlds in ways gravity alone should be able to explain. Planet 9, still invisible ...

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. Labelled as planet X, prominent astronomers ...

A team of astronomers from Taiwan has uncovered promising evidence suggesting the existence of Planet 9, a hypothesized planet beyond Pluto in the far reaches of our Solar System. This new potential ...

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 ...