Planet 9 and the Weird KBO Orbits . The idea of a ninth planet existing at the edge of the solar system, far beyond Neptune, was put forward in 2014.

THE HUNT FOR MYSTERIOUS PLANET 9. In October 2017, Batygin said that there are "five different lines of observational evidence" that point to the existence of Planet Nine.

Planet 9: Everything we know about this new mysterious dark world. The gas-giant planet is believed to be ten times the mass of Earth and as big as Neptune. Steve Connor. Science Editor.

Planet 9, which NASA calls Planet X, “orbits our Sun in a highly elongated orbit far beyond Pluto.” For a fleet of tiny probes to reach it in just a decade would indeed be revolutionary.

Planet 9: Secret, dark world possibly hiding within our solar system. The mysterious object has been spotted disturbing the movement of smaller objects in the outer solar system — but is too far ...

Planet 9 likely isn't a stolen exoplanet after all. New research shows the probability of ideal planet-swapping positions between young stars is near zero.

Planet 9 may be closer and easier to find than thought—if it exists. A new study's "treasure map" suggests that a planet several times more massive than Earth could be hiding in our solar system ...

Researchers working on the Planet 9 question have uncovered some intriguing options for our potential distant planet. If it exists, it might not be from our neighborhood at all.

Almost a decade after astronomers proposed the existence of Planet 9, an unseen extra planet in the distant reaches of the solar system, they still haven’t all agreed whether it’s real or not ...

While Planet 9’s existence remains fully up in the air, more evidence could become available within a year or two, when a Chilean observatory that’s currently under construction opens, ...

If Planet 9 exists, it makes sense that it could have formed around another star and then been captured by the gravitational pull of our sun. For one thing, the eight confirmed planets and dozens ...

At the moment, Planet 9 still a theory. It won’t be named until scientists can confirm its existence with pictures. If and when that happens, it will be up to the members of the International ...