Orbital mechanics is a cornerstone subject for aerospace engineering students. Maintaining the focus of the first edition, the author provides the foundation needed to understand the subject and proceed to advanced topics. Starting with the solution of the two-body problem and formulas for the different kinds of orbits, the text moves on to Kepler's equations, orbits in three dimensions, orbital elements from observations, orbital maneuvers, orbital rendezvous and interplanetary missions. This is followed by an introduction to spacecraft dynamics and a final chapter on basic rocket dynamics. The author's teach-by-example approach emphasizes the analytical procedures and computer-implemented algorithms required by today's students. There are a large number of worked examples, illustrations, end of chapter exercises (with answers) as well as many MATLAB (R) programs for use in homework and projects. The text can be used for one and two semester courses in space mechanics.