Presentation #502.01 in the session “TNOs and Planet X”.
A 9th massive planet in the outer region of the solar system has been proposed as an explanation for unexpected features in the orbital distribution of extreme Trans-Neptunian objects (TNOs). This 9th planet can cause TNOs to be deposited in regions of the Kuiper belt that would otherwise not be populated due to interactions with the known 8 planets alone. Using N-body simulations, we find that this is the case for distant, detached TNOs at low inclination. In the 8-planet model, Kozai-Lidov oscillations of TNOs in mean motion resonances (MMR) with Neptune are the main mechanism to populate the distant, detached region. This mechanism, however, only deposits TNOs with high inclinations into this region. In the 9-planet models, the 9th planet can populate this low inclination region with secular interactions that are not limited to high inclination orbits. Our simulations show that the relative numbers of high and low inclination bodies are quite sensitive to the presence of a 9th distant planet, and this region of TNO orbital space may provide important new constraints on any undetected planet in the distant solar system. With more detected objects observed in the coming years, this region of the Kuiper belt can help us gain a better understanding of the dynamics of the distant solar system.