Spacecraft Mission Design, Second Edition takes the shortest route to practical understanding of mission design. It focuses on the most general and most practical tools needed for the early spacecraft design studies, including the principles of two-body motion, definition of orbits, orbital maneuvers, and central body observation. The use of elementary mathematics makes this concise book ideal for upperclass college students, graduates, and practicing engineers or managers. There are enough worked examples that one can be self taught. This second edition includes astronomical reference material and sections on constellations, lunar trajectories, and cycler orbits. ORBWIN allows you to proceed directly from understanding into professional work. It provides the accuracy, speed, and convenience of personal computing. It defines all orbital elements for any orbit, provides the parameters at any orbital point, calculates spacecraft horizon, instrument field of view, orbit perturbations, ground track, planetary ephemeris, conversion of Julian days, oblique triangle solutions, and propellant weight projections. Any major body in the solar system may be used as the central body.