The Scattered Disk: Origins, Dynamics, and End States

From a review of the methods that have been used so far, we estimate the present mass of the scattered disk to be in the range 0.01 to 0.1 M . We review the dynamics of the scattered disk, paying special attention to the mean-motion and Kozai resonances. We discuss the origin of the scattered objects both as coming from the Kuiper belt and as remnants of the scattering process during Neptune’s migration. We stress the importance of the mean-motion resonance coupled with the Kozai resonance in raising the perihelia of scattered disk objects, emphasizing that fossil and live high perihelion objects could thus have been produced. We analyze other mechanisms that could have implanted the detached scattered objects onto their current orbits, focusing on a few that demand specific explanations. We explore the different end states of scattered disk objects and highlight the importance of their transfer to the Oort cloud.