TABLE OF CONTENTS This chapter provides an introduction to, and an overview of, the orbit perturbations, the perturbing sources, and the physical phenomena associated with orbital motion. Simplified examples and key equations should give readers an easy-to-access reference for understanding and solving typical perturbation problems.
Chapter 9 provides an in-depth description of the mathematical foundations and derivations of the perturbing functions and equations. Chapter 10 gives more detailed descriptions and discussions on various perturbing sources and their special effects on orbital motion. The chapter also includes actual examples of mission analysis and design utilizing the unique orbit-perturbation properties.
What are orbit perturbations? By definition, those small deviations from the two-body orbit motion are called orbit perturbations. The two-body orbit motion can be expressed by the conic solutions (ellipse, hyperbola, and parabola) in closed form, which has been explained in detail in Chapters 3 and 4. The equations of two-body motion and its solutions were derived through Newton's law of gravitation and Kepler's laws of orbit motion under the assumption of point mass or mass with spherically symmetrical distribution.
The equations of motion of a two-body problem can be given in the relative form as
| (8.1) |  |
where r is the position vector of the satellite measured from the center of the primary body, and ? is the gravitational constant of k 2 ( m 1 + m 2).
Because of the presence of various perturbing forces, Eq. (8.1) can be used only...
