An Analysis of the Accessibility of Earth-Approaching Asteroids.

The purpose of this thesis is to analyze the accessibility of Earth-approaching asteroids using a computer program that was practical to run on a microcomputer. This analysis employs techniques that can easily be adapted to find optimal trajectories for a variety of orbital intercept applications. The mathematical analysis was adapted from recently developed algorithms that were designed to run on main frame computers using extensive software libraries and data resources. The computer program developed for this paper was designed to operate on an IBM PC equipped with an 8087 math co-processor chip. Programming was done in Turbo PASCAL Version 3.0 which supports the 8087 mathematical capabilities. The program was designed to be self contained except for data files of orbital elements. The program was also designed to operate efficiently and quickly while retaining much of the accuracy found on the main frame implementations. Only nonperturbed Keplerian motion was modelled. Every effort was made to ensure the program was as flexible as possible. Any object in the solar system in heliocentric orbit can be used as either the departure or arrival body. Orbital element data files are included for all the planets, several periodic comets, all the recently discovered Earth-approaching asteroids, and many of the main belt asteroids. This flexibility permits not only rendezvous missions to be calculated, but can just as easily handle fly by trajectories and return-to-Earth missions.