The writing is crisp and clearly written by someone who is aware of the conceptual difficulties that nonscientists have in coming to grips with relativity.

    The final chapter briefly discusses the future Apollo program.

    They were initially assembled by Edgar M. Cortright, a senior official of the National Aeronautics and Space Administration, as a personal reminder of the stirring years when man first developed the ability to propel his cameras and instruments, and then himself, beyond the Earth's atmosphere. With this publication, they become a part of NASA's flow of reports to the American public on some of the growing returns from its investment in the exploration of space. As such, I hope this book can find its way into many American homes, for it is a part of a record of achievement of which our country can be proud."

    Clayton's Principles of Stellar Evolution and Nucleosynthesis remains the standard work on the subject, a popular textbook for students in astronomy and astrophysics and a rich sourcebook for researchers. The basic principles of physics as they apply to the origin and evolution of stars and physical processes of the stellar interior are thoroughly and systematically set out. Clayton's new preface, which includes commentary and selected references to the recent literature, reviews the most important research carried out since the book's original publication in 1968.

    He also covers the other Gemini flights and briefly discusses the future of the Apollo program.