Learn how a possible ninth planet, the theoretical Planet X, could have acquired its wide orbit in the outer Solar System - a ...

Astronomers have just discovered a new celestial body in our solar system that could challenge major space theory. 2017 OF201 ...

It's an evocative idea that has long bedevilled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. "OF201 is, in ...

Cheng, together with graduate students from Princeton University, discovered the potential dwarf planet while searching for ...

Planets with unusually wide orbits may be normal by-products of the formation of planetary systems. This is suggested by new simulations.

Scientists are intrigued after spotting a highly unusual celestial object lurking at the very edge of our solar system.

Astronomers have discovered a new dwarf planet, named 2017 OF201, far beyond Pluto's orbit. It takes 25,000 years to orbit ...

The newly discovered object, named 2017 OF201, has a 25,000-year orbit and is believed to be a large contender for dwarf ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system.

Hunting for the building blocks of life? Located in the asteroid belt, Ceres is likely a good bet, study finds ...

The International Astronomical Union’s Minor Planet Center, which catalogs new moons and other small bodies in the solar ...

Scientists have discovered a mysterious new object far beyond Neptune, and it could be one of the most distant dwarf planets ...