Astronomers have picked up evidence of an Earth-sized world, distinct from the previously hypothesised Planet Nine and Planet ...

Astronomers propose a new hypothetical planet, Planet Y, beyond Neptune, based on observed orbital anomalies in the Kuiper ...

A study suggests an Earth-sized planet, dubbed Planet Y, may exist beyond Neptune, affecting the orbits of icy objects in the ...

A mysterious new world may be hiding in the outer reaches of our solar system. According to arecent study published on arXiv ...

A recent study hints at a previously unknown Earth-sized planet, dubbed Planet Y, potentially influencing gravitational distortions in the outer solar system.

The Psyche spacecraft is on a six-year journey to reach a metal-rich asteroid by the same name. Well into its voyage, the ...

In 2005 the dwarf planet Eris was found orbiting the Sun at distances beyond the Kuiper Belt in yet another new region of the solar system that astronomers call the Scattered Disk.