Astronomers searching for a ninth planet in our solar system say they've found a "good" candidate far beyond Neptune, according to a new preprint study. This could be humanity's first glimpse at the ...

There has been a lot of back and forth about the existence of a mysterious ninth planet, often referred to as "Planet Nine" or even "Planet X." Now, though, researchers say there is likely at least a ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...

It's an evocative idea that has long bedeviled 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. Some astronomers ...

The solar system consists of our star, the sun, and everything bound to it by gravity: the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, along with dwarf planets like ...

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.

Does our solar system have a mysterious ninth planet? The discovery of a new dwarf world suggests not. It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is ...

A ninth planet is one form the solar system’s mysterious mass could take. (Caltech/R. Hurt (IPAC)/) After centuries of watching the skies, the map of our local solar system has grown quite detailed.

Prefer Newsweek on Google to see more of our trusted coverage when you search. Good news for those with a Pluto-shaped hole in their life, as astronomers may be on the verge of finding a new ninth ...