Long-Term Evolution of Highly-inclined Trans-Neptunian Objects

The efficiency to capture long-period comets, originated from the distant Oort cloud, into short-period comets is very low, especially for those originally in high-inclination or retrograde orbits. Therefore, it is believed that Trans-Neptunian Objects (TNOs) is the source of short-period comets. However, the recent discovery of co-planar TNOs in high-inclination orbits (Chen et al. 2016) raises interesting question on their origins, namely, when and how they were injected into the current orbits, their evolution histories, and their dynamical lifetimes. Is it possible that these co-planar TNOs were from a a small population which originally had highly-inclined/retrograde orbits when the Oort Cloud was formed? To explore this issue, we examine the associated dynamical evolution by long-term orbital integration. We present the statistical results for this numerical exercise here.