Planet Nine should appear stationary over the course of a single day but show detectable movement over months.

A team of astronomers from Taiwan has uncovered promising evidence suggesting the existence of Planet 9, a hypothesized ...

In an exciting breakthrough in planetary science, a recent study has increased the likelihood of Planet Nine’s existence by up to 40%. This planet, also referred to as Planet X, has remained an ...

Since 2016, the suggestion that there might be a ‘Planet Nine’ within our solar system has rapidly transformed from left-of-field thinking to a scientific possibility.

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today ...

Astronomers have found 2023 KQ14, nicknamed Ammonite, a rare sednoid with a unique orbit that challenges the Planet Nine hypothesis.

Planet Nine is a hypothetical planet, first theorised by astronomers from California Institute of Technology (Caltech) back in 2016. Said to have a mass about five to 10 times that of Earth, this ...

A giant, shepherd planet. The existence of a ninth major planet at the farthest reaches of our solar system was first proposed in 2014 to account for many of the strange orbits we see in other ...

On Planet Nine, the conditions would arguably be even worse. The study, still on the pre-print server arXiv as it awaits peer review, found that Planet Nine is so far away from the sun, ...

Astronomers have a potential Planet Nine candidate, detected via infrared radiation. This candidate's orbit is very different from what's predicted for Planet Nine. The candidate may be a false ...

But even if it doesn't spot Planet 9 directly, the Rubin Observatory might find some more minor planets, ones whose orbits might be affected by Planet 9. And that could provide additional evidence ...