Astronomers are on the trail of something big. Their target is between 5 and 15 times the mass of Earth and orbits the sun beyond Neptune. This is Planet 9, the last undiscovered orbiting body in ...

While the paper associates Planet 9 with a primordial black hole of 0.5 to 20 times Earth's mass, Loeb said he finds this hard to believe.

If Planet 9 Is Actually a Black Hole, It Completely Changes How We Understand Our Universe. And get this: The thing could be smaller than a soccer ball.

And they're hoping that using this new method, they'll be able to figure out whether Planet 9 is actually a planet or a black hole. Their study was accepted for publication in The Astrophysical ...

Astronomers confirm ‘lite intermediate’ black holes, too large for ordinary stars, revealing clues about early stellar ...

Neutron stars are timelike matter with a maximum mass of about 2.34 solar masses in quantum chromodynamics (the strong color ...

Others thought that the shepherd was actually a small black hole instead of a giant planet. More recently, two astronomers in Japan proposed that a different planet , instead of Planet 9, might be ...

This is a galactic-sized problem. Scientists revealed Tuesday that galaxy PBC J2333.9-2343 has been reclassified after discovering a supermassive black hole that is currently facing our solar ...

MOND and a far flung Planet 9 are far from the only hypotheses vying to explain the strange orbits of Sedna and its companions. Some astrophysicists, for example, think a miniature black hole ...

A primordial black hole in the solar system (illustrated) could make its presence known by altering the orbits of planets. Benjamin V. Lehmann, with use of SpaceEngine@Cosmographic Software LLC ...