USA in Space collects 280 essays on the major space programs, piloted and robotic missions, satellites, space centers, space planes, and issues from the earliest missions to the present. The many changes in the space program over the past half decade made a careful reading of every page necessary to ensure the content's accuracy. USA in Space, Third Edition updates the Second Edition (3 vols., 2001) with 42 new essays plus 5 replaced essays for a total of 280 essays.