A 2016 hypothesis suggests that this mysterious ninth planet, long hidden from the scientific world, could offer unexpected lessons about the nature of gravity and the dynamics of the solar system.
The essence of the hypothesis is that Planet Nine should be a massive planet, about 10 times more massive than Earth, located somewhere in the distant outskirts of the solar system.
This hypothetical planet has been proposed as an explanation for the strange orbits of objects in the Kuiper Belt beyond Neptune. These objects appear to be moving in the opposite direction to the planets in our solar system, raising many questions among astronomers.
Since then, astronomers have made great efforts to find Planet Nine, but so far have been unsuccessful. The search was carried out carefully, and almost half of the night sky was studied, but the mysterious planet still remained hidden.
But now new research has emerged that raises even more questions about the existence of Planet Nine. Researchers have presented a surprising hypothesis: what if Planet Nine is not a planet at all, but rather another type of gravity that masquerades as a planet?
According to this new theory, inconsistencies in the motion of objects in the outer regions of the Solar System can be explained by modified Newtonian dynamics (MOND).
According to MOND, then, Kuiper Belt objects are actually being pulled by the rest of our galaxy, rather than by an undiscovered planet.
“MOND is really good at explaining galactic-scale observations,” study author Harsh Mathur, a theoretical physicist at Case Western Reserve University in Ohio, said in a statement. “But I hadn’t expected that it would have noticeable effects on the outer solar system.”
This means that the mysterious force supposed to be caused by Planet Nine may actually be the result of changes in our understanding of gravity and dynamics.