Advances in Space Science, Volume 2 brings together research and developments in the astronautical sciences. This volume is composed of six chapters on space physics, tracking, materials, electrical propulsion systems, and attitude control. The introductory chapter considers selected examples of experimental areas suitable for investigation by means of space vehicles, with emphasis on high altitude satellites and space probes. The succeeding chapter examines the purposes of satellite tracking, several major tracking systems, problem of tracking lunar and planetary probes. Another chapter surveys the general problem areas with respect to space materials. These topics are followed by two chapters on plasma propulsion devices and electrostatic propulsion systems for space vehicles. The concluding chapter discusses the principles of altitude control of satellites and space vehicles. This book will prove useful to space scientists, engineers, and researchers.