Mystery Planet in the Outer Solar System Astronomers have long been intrigued by the possibility of hidden planets beyond Neptune. A recent study introduces a new contender, tentatively called Planet Y, as a possible explanation for unusual orbital tilts observed in objects located in the Kuiper Belt—a vast region of icy bodies stretching past the orbit of Neptune. Although Planet Y hasn't been directly seen, its existence has been proposed based on the unexpected tilt in the orbits of