Dynamics Study Of The Kuiper Belt Objects

The dynamics study of the Kuiper Belt Objects (KBOs) is one of the research front fields in the Solar System dynamics nowadays. In the Kuiper belt there is the most primordial information, which may lead to the more deepgoing understanding of the early history of the Solar System. A comparison of the observed orbital properties of KBOs with theoretical studies provides the abundant first-hand clues to the formation and evolution of the outer Solar system. The study of dynamical structure of KBOs that have mean motion resonances with Neptune would make for revealing exceedingly rich mechanism of resonant KBOs and understanding resonant formation and evolvement mechanism and inherent relation between this mechanism and the outer Planet's formation and evolvement.In this paper, we studied formation and dynamics evolution of KBOs by adopting restricted three-body problem dynamics models of celestial mechanics and using numerical method on the basis of the analysis of the observed orbital distribution properties of KBOs. This paper consists of four chapters.In Chapter 1, we explained the background and significance for studying dynamics of KBOs, introduced the current research state and development trend for the important study subject at present.In Chapter 2, we made data processing for the observed orbital elements of KBOs, analyzed orbital semimajor axis, eccentricity and inclination distribution properties of them. We found that KBOs congregate in resonance region, their eccentricity are bigger than classical KBOs, but some classical KBOs have high inclination, and scattered KBOs distribute in the region where objects perihelion distance are from 30AU to 45 AU.In Chapter 3, we established restricted three-body problem physical model that only contain Sun, Neptune and a KBO, neglected perturbation of other major planets and KBOs.Beginning from perturbation motion equation of KBOs with orbital elements as variable, we introduced high precision, automatic select steps eight Runge-Kutta-Fehlberg single step integrator to simulate dynamical evolvement of KBOs. First, we integrated the evolution of quadruplet 751 test particles in 35-5OAU region of Kuiper belt on 107yr and 108yr time scales respectively, with different initial orbital elements, and discussed initial orbital semimajor axis, eccentricity and inclination's influence to the evolvement of KBOs. Secondly, we made numerical simulation to the future evolvement of the observed resonant KBOs and classical KBOs within 39AU over 108yr time scales, studying dynamical evolvement behavior of these objects from orbital semimajor axis, eccentricity and inclination. It showed that some resonant objects, particularly 3:2 orbital resonant, have short dynamical lifetime and instability. The dynamical evolvement of some objects should be irregular, even though they have stable orbit over lOyr time scales. The orbit of observed classical KBOs in 36-39AU is very stable.The chapter 4 is conclusion and discussion. We summarized the important conclusions obtained in the paper and forward new questions awaited study in the future.