A telescope has discovered a new world on the edge of the Milky Way – potentially confirming the ‘Planet X’ theory. Beyond Neptune, a smaller ‘ninth’ planet has been identified in the Kuiper Belt. If ...

Astronomers used a telescope in Hawaii to find a new object on the outer edges of our solar system, helping to fuel evidence of a long-standing theory about Planet Nine, or Planet X. For years, ...

Discovery of 2017OF201, a large trans-Neptune Object, challenges previous beliefs about the Kuiper Belt and hints at the ...

Astronomers have been searching for evidence that Planet Nine exists for years Becca Longmire is a digital news writer-reporter at PEOPLE. She has been working at PEOPLE since 2024. Her work has ...

European astronomers report the discovery of a second alien world in the TOI-1422 planetary system located some 500 light ...

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 ...

The cold and mysterious Oort cloud at the edge of our solar system may be hiding a rogue exoplanet, new research suggests. When you purchase through links on our site, we may earn an affiliate ...

On a chilly morning in February 1930, a young astronomer named Clyde Tombaugh was hunched over a blinking comparator at the ...