Theses

This dissertation discusses research that focuses on understanding transneptunian objects (TNOs) using a variety of techniques and approaches. In Chapter 1, I introduce the main concepts used throughout this dissertation and discuss the current understanding of the transneptunian region. In Chapter 2, I discuss my efforts to understand how Neptune's late stages of migration affect the Haumea family, the only known collisional family in the transneptunian region. Using advanced simulations of Neptune migration, I find that the Haumea family can plausibly form before the termination of giant planet migration and show that this extensively mixes the family. The simplest explanation for the formation of Haumea and its family is a slow disruption of a large, primordial binary system. In Chapter 3, I examine the detectability of non-Keplerian effects in the mutual orbits of transneptunian binaries. I find non-Keplerian effects are common, with 20% of TNBs best explained by a non-Keplerian orbit. I also demonstrate that one of the components of TNB (66652) Borasisi-Pabu is a contact binary. In Chapter 4, I examine the non-Keplerian orbits of Hi'iaka and Namaka, the satellites of Haumea, showing that they are strongly affected by both inter-satellite gravitational interactions and precession caused by Haumea's nonspherical gravitational field. Future observations of the Haumea system, combined with non-Keplerian fitting, will sensitively probe Haumea's interior. Lastly, in Chapter 5, I explore the mutual orbits of Cold Classical TNO binaries using non-Keplerian orbit fitting. Out of a sample of 18 binaries, 6 have significantly non-Keplerian orbits, allowing detailed characterization of their system architecture. I find that 3 of these systems are best explained as hierarchical systems, while the remaining 3 are consistent with precession due to the Sun's gravitational influence. The hierarchical systems I find strongly support the streaming instability theory of planetesimal formation.

Orbital systems of two or more Trans-Neptunian Objects (TNOs) are valuable for investigating formation processes of the early Solar System. Because TNOs exist below the diffraction limit of current telescopes, they are rendered as point spread functions (PSFs) in observational images. To correctly understand the orbital dynamics of TNO systems, the PSFs must be modeled according to telescope, camera, and observational parameters. These models can then be fit to images to produce the precise relative astrometry that is needed to fit the orbits. The software package nPSF was designed to fit modeled PSFs to images containing an n number of PSFs using Bayesian parameter inference methods, specifically the Markov Chain Monte Carlo process. The relative astrometry of the system can then be derived from the posterior distribution. We test the capabilities of nPSF by fitting images of 2PSF Trans-Neptunian Binaries and comparing our results to the published astrometry for those systems. We show that nPSF produces good astrometry in the tested systems. Additionally, we apply nPSF to the search of a tertiary object in various potential hierarchical triple systems. The results produced by nPSF do not indicate the detection of a third component in these systems.

Asteroids and other small objects throughout the Solar System are known to exhibit many of the oddities of classical Newtonian gravitation, and these oddities vastly increase the difficulty of analysis in N-body modeling and simulation. Recently, there has been developments in the study of binary asteroids which orbit each other simultaneously in the broader Sun-Planet field. We use a modified four-body model to analyze the evolution of two asteroids in a broader field of two primaries of arbitrary mass. We show the existence of relative equilibria and periodic orbits of Hill, Comet, Lyapunov, and Binary type in our model. We also present the spectra of the reported equilibria.