New discoveries of objects in the Kuiper Belt have also presented challenges for the Planet Nine theory. The latest is known ...

There are currently no other explanations for the effects that we see, nor for the myriad other P9-induced effects we see on ...

Astronomers have long speculated about the existence of a mysterious planet lurking far beyond Neptune, a world several times ...

Discover the mystery of Planet Nine, the elusive celestial body beyond Neptune. Explore the latest astronomical evidence and theories as scientists inch closer to finding this potential ninth planet ...

A newly discovered dwarf planet called 'Ammonite' (2023 KQ14) has been spotted in the outer solar system, and it could be another nail in the coffin for the Planet Nine hypothesis.

If Planet 9 exists, a similar scenario may have played out in the early days of our Solar System, with Jupiter's gravity pushing it toward the edge, only for it to be saved by another, alien star.

In October 2017, NASA released a statement saying that Planet Nine may be 20 times further from the Sun than Neptune is, going so far as to say "it is now harder to imagine our solar system ...

If Planet 9 is real, this observatory has around a 70 to 80 percent chance of finding it, he estimates, adding that it's not a sure thing because there are so many uncertainties.

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.

“Planet Nine” could explain the seemingly puzzling orbits traced by two of the distant worlds, known as Sedna and 2012 VP113 (which has been nicknamed “Planet Biden” in homage to a ...