PARIS - It’s an evocative idea that has long bedevilled scientists: a huge and mysterious planet is lurking in the darkness ...

A US-based trio hunting "Planet Nine" has instead stumbled on what appears to be a new dwarf planet in the solar system's ...

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

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

Located 15,000 light-years away in a region of the Milky Way brimming with stars, gas and dust, this object could be a highly ...

A planet twice the size of Jupiter has been confirmed in Nu Octantis. Its retrograde orbit and origin raise new questions about planetary formation in binary systems.

People always want to know what will happen to Earth when the sun eventually swells up as a red giant. For one thing, the ...

Astronomers confirm the existence of small, hot and likely rocky planets by observing the subtle gravitational wobbles of the star they orbit Researchers supported by the U.S. National Science ...

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 ...

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

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