Scientists' hunt for a mysterious planet at the edge of our solar system might have turned up results. A US-trio appears to ...

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

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

Discovery of a possible dwarf planet suggests our cosmic backyard holds many more secrets to uncover It is an evocative idea ...

Spotted beyond Neptune, the newly identified object follows an odd path through space, one that complicates a decades-old ...

A US-based trio hunting this elusive world has stumbled on what appears to be a new dwarf planet in the solar system's outer ...

Some astronomers say the strange, clustered orbits of icy rocks beyond Neptune indicate that something big is out there, ...

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

Simulations show that the stars’ tug could send Mercury, Venus or Mars crashing into Earth — or let Jupiter eject our world from the solar system.