Dynamical Harassment of the Kuiper Belt During Planet Migration and Instability

NASA Emerging Worlds

Start Date: 08/16/2023
Project #: 1930
End Date: 08/15/2026
Award #: 80NSSC23K0771
Project Description

Accurately understanding how the modern Kuiper belt’s properties are connected to the early dynamical evolution of the outer solar system is critical to deciphering our solar system’s history and formation. Here we propose a series of numerically driven studies that will markedly improve this understanding. First, we will directly model how giant planet orbital instabilities driven by a dispersing primordial planetesimal disk excite (or fail to excite) the orbits of the Kuiper belt’s in situ cold classical belt subpopulation. Second, we will simulate how the most massive members of the dispersed primordial disk affect the overall structure of the modern Kuiper belt. Third, we will model the evolution of the cold classical belt’s binaries as they suffer impacts and close encounters with members of the primordial planetesimal disk during its dispersal. Utilizing state of the art techniques in simulating dynamics and observing biases, our proposed work will place new stringent constraints on the possible orbital evolution of Neptune as well as quantify the influence that ejected planets and Pluto mass bodies have had on the cold classical belt’s orbital excitement. In addition, our work will place the tightest constraints developed to date on the masses and numbers of the largest planetesimals in the early outer solar system. Finally, our work will be the first to quantify how the dispersal of the outer solar system’s massive primordial belt altered the distribution of binary objects in the cold classical belt, and it may lead to a reassessment of the primordial nature of these binaries’ orbits. Taken as a whole, our proposed research is a major advance in understanding the relationships between the modern Kuiper belt and the dynamical processes that generated it and the broader outer solar system.