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

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

It's the dawn of a new era for American Airlines. The carrier is making perhaps its biggest investment yet in premium, ...

A newly identified dwarf planet, named 2017 OF201, has been discovered in the distant outer reaches of 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 ...

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.