""Space Trajectories"" by T.C. Helvey is a comprehensive guide to the mathematical principles and techniques necessary for designing and analyzing spacecraft trajectories. The book covers a wide range of topics, including the fundamentals of celestial mechanics, orbit determination and propagation, interplanetary transfers, and trajectory optimization. The author provides detailed explanations of the underlying physics and mathematics, as well as practical examples and exercises to help readers develop their skills. The book is aimed at engineers, scientists, and students with a background in mathematics and physics who are interested in the field of space exploration. It is an essential resource for anyone involved in the design and operation of spacecraft, as well as for researchers and educators in the field of aerospace engineering.This scarce antiquarian book is a facsimile reprint of the old original and may contain some imperfections such as library marks and notations. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions, that are true to their original work.