For instance, Neptune migrated outward, switching places with Uranus, and pushed a lot of the small, icy bodies into the ...

Scientists have recently spotted a huge object far away in the cold outer reaches of our solar system. This ...

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

Scientists have identified an object about 435 miles (700 kilometres) wide inhabiting the frigid outer reaches of our solar ...

Scientists have discovered a colossal object approximately 435 miles wide in the frigid outer reaches of our solar system, ...

Astronomers announced the discovery of a new dwarf planet, provisionally named 2017 OF201, located in the remote outskirts of ...

A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the ...

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

As it orbits the sun once every 25,000 years, the celestial body 2017 OF201 travels beyond the Kuiper Belt into a region ...

U.S. astronomers hunting for "Planet Nine" have instead stumbled on what appears to be a new dwarf planet in the solar system's outer reaches.

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...