Devised for a quantitative understanding of the physics of the universe from the solar system through the milky way to clusters of galaxies all the way to cosmology, this acclaimed text offers among the most concise and most critical ones of extant works. Special chapters are devoted to magnetic and radiation processes, disks, black-hole candidacy, bipolar flows, cosmic rays, gamma-ray bursts, image distortions, and special sources. At the same time, planet earth is viewed as the arena for life, with plants and animals having evolved to homo sapiens during cosmic time. This text is unique in covering the basic qualitative and quantitative tools, formulae as well as numbers, needed to for the precise interpretation of frontline phenomena.