<Tr> <Th> Mean radius </Th> <Td> 13,000 to 26,000 km (8,000--16,000 mi) 2--4 R (est .) </Td> </Tr> <Tr> <Th> Mass </Th> <Td> 7025600000000000000 ♠ 6 × 10 kg (est .) ≥ 10 M (est .) </Td> </Tr> <Tr> <Th> Apparent magnitude </Th> <Td>> 22.5 (est .) </Td> </Tr> <P> Planet Nine is a hypothetical large planet in the far outer Solar System, the gravitational effects of which would explain the improbable orbital configuration of a group of trans - Neptunian objects (TNOs) that orbit mostly beyond the Kuiper belt . </P>

Orbital period of a planet 10 au from the sun