Planet Nine Planet Nine Planet Nine is a hypothetical planet in the outer region of the Solar System. Its gravity could explain the unlikely clustering of orbits for a group of extreme trans-Neptunian objects (eTNOs) that orbit beyond Neptune with average distances greater than 250 AU. These eTNOs tend to have their points of closest approach to the Sun clustered in one direction, and many of their orbits have a similar tilt. This evidence suggests that the gravity from a large undiscovered object is influencing the orbits of the most distant known Solar System objects. This undiscovered super-Earth-sized planet would have an
Uranus of our Solar System." In recognition of his achievement, King George III gave Herschel an annual stipend of £200 on condition that he move to Windsor so that the Royal Family could look through his telescopes. The name of Uranus references the ancient Greek deity of the sky Uranus (), the father of Cronus (Saturn) and grandfather of Zeus (Jupiter), which in Latin became "Ūranus" (). It is the only planet whose name is derived directly from a figure of Greek mythology. The adjectival form of Uranus is "Uranian". The pronunciation of the name "Uranus" preferred among astronomers is ,