Is The Planet X or Nine Actually a small black hole in Our Solar System?

For nearly 5 years, growing numbers of scientists have blamed the weird orbits of distant solar system objects on the gravitational effects of an as-yet-undiscovered “Planet Nine” that lies in the icy realm far beyond Neptune. But a pair of physicists is now floating an intriguing idea that could offer a new way to search for the object: What if that supposed planet is actually a small black hole?