Yet another study promising to help us find a planet beyond the orbit of Pluto fails. So, where exactly is Planet Nine? And why haven't we found it?

Astronomers looking into the orbits of Kuiper Belt objects may have found a flaw in data we thought pointed to the existence of a large planet beyond Neptune's orbit.

According to sensationalistic headlines, the hypothetical ninth planet in our solar system is a tennis ball sized black hole. According to physics, it's far more likely to be literally anything else.

A recent paper imagines a new explanation for the strange motions of Trans-Neptunian Objects observed by astronomers for the last 200 years, but it doesn't mean that we won't still search for Planet Nine.