In January, astronomers revealed evidence for the potential existence of another planet in the solar system. Researchers suggest that if this world — dubbed Planet Nine — exists, it could be about 10 times Earth's mass and orbit the sun at a distance about 500 times the distance from the Earth to the sun. Previous research suggested that Planet Nine would possess a highly tilted orbit compared with the relatively thin, flat zone in which the eight official planets circle the sun. This led scientists to investigate whether Planet Nine's slant might help explain other tilting seen elsewhere in the...