Interplanetary Flight

Abstract

In fact, the first problem---to determine the orbit in the spheres of influence of different celestial bodies---is so serious that we cannot solve it exactly with analytical means. Hence, in practice, all interplanetary flights are determined only by complex numerical simulations. This enables one also to take even more complex situations into account, such as the so-called gravity-assist, weak stability boundary maneuvers, which we will discuss later, or even invariant manifolds (see Sect. 11.5.2). But as the important goal here is the basic understanding of orbit mechanics, we are seeking for a method to essentially describe the processes, albeit not precisely. This is indeed possible. The method is called ``patched conics.''