A direct descent is one in which the main descent propulsion system burns continuously from lunar approach to touchdown. The characteristic velocity requirement for direct lunar descents is presented as a function of the landing site location relative to the normal impact point. Results are included for translunar trip times of 60, 75, and 90 hours, for specific impulses representative of both Earth storable and cryogenic propulsion systems, for landing sites located anywhere on the lunar surface, and for ignition thrust-to-Earth weight ratios between 0.12 and 10.0. The data presented are useful in determining approximate performance capability and in evaluating tradeoffs during preliminary mission planning studies.

Lunar Base Handbook provides an overview about the Moon and its environment, the current status of lunar base design, tools we need to design a lunar base, checklists and flow charts that outline the design process, and technological requirements of a lunar base. The main audience for this book is engineers, but it is also interesting for scientists, managers, lawyers, undergraduates, and high school students, and readable for the interested layman.