The solar system lost its ninth planet back when Pluto was demoted to a dwarf planet, but research might indicate that there ...

It’s been nearly 2 centuries since a planet was discovered in the solar system. But now scientists think they’ve uncovered evidence of a newcomer that just might usurp that honor from Neptune.

A Jupiter-like planet has been found orbiting a young sun-like star in a solar system far away in what is a potentially ...

The coldest planet in the Solar System is Uranus, which is surprisingly colder than Neptune due to its unique internal heat ...

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Astronomers have uncovered a massive new trans-Neptunian object, 2017 OF201, lurking at the edge of our solar system. With an orbit stretching 25,000 years and a size that may qualify it as a dwarf ...

I/ATLAS is a fast, ancient interstellar object. Its odd features fuel both scientific study and speculation. On July 1, ...

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

Astronomers have directly spotted a rare young planet, WISPIT 2b, still forming within the gap of a dusty ringed disk around a star like our sun—something long theorized but never observed until now.