We still don't know for sure if there's a ninth planet in our solar system, but a new discovery could help to prove that ...

A tiny object far beyond Pluto, newly discovered by the Subaru Telescope, could reshape our understanding of the early Solar ...

Learn more about a sednoid called Ammonite that has been detected in the outer reaches of the Solar System.

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

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

In the icy, dark expanse beyond Neptune, a cosmic fossil has surfaced that threatens to upset decades-old assumptions about the solar system’s secret structure. The new discovery of “Ammonite,” a ...

Researchers use the Subaru Telescope in Hawaii to find a small object on the outer edge of the Solar System. Nicknamed ...

Science | NPR If Planet Nine is out there, this telescope might actually find it A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some ...

If Planet Nine is finally discovered, as one of those who first postulated its existence, does Brown have any suggestions for a possible formal name for this new member of the solar system?

Researchers from Rice University claim to have fresh evidence of Planet Nine - as well as a method to find it.

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.