"Astronomy and Astrophysics is a comprehensive, fundamental, up-to-date reference book. It is filled with vital information and basic facts for amateur astronomers and professional astrophysicists, and for anyone interested in the Universe, from the Earth and other planets to the stars, galaxies and beyond. Although serious and thorough, the language, and ideas will attract the general reader, as well as students and professionals. "Astronomy and Astrophysics consists of two main parts, a Timeline and a Dictionary. The Timeline is a concise history, arranged chronologically, which provides the complete story of cosmic discovery from early Chinese and Greek astronomy to the latest findings of modern astrophysics and robotic spacecraft. It provides a sense of destination and flow in our growing awareness of the Universe. Each entry in the unfolding narrative is written in a concise, light and friendly style, without being weighted down with incomprehensible specialized terms. The Glossary defines all terms and acronyms related to our celestial science, from important concepts to individual objects and space missions. It is arranged alphabetically and complemented by numerous tables of fundamental data for luminous, well-studied cosmic objects, including the celestial coordinates required to observe them. Line drawings with clear labels and captions are also used to compact a scientific insight. A concise Index cross-references concepts, discoveries, ideas, people, history and time in both the Chronology and Glossary.