One of the most vigorous sciences of our time, astrophysics constantly changes under the impact of new discoveries about everything from our own sun to the most distant and exotic of extragalactic phenomena. In chapters written especially for this volume, twelve distinguished scientists actively pursuing astrophysical research offer up-to-date reviews and commentary on new developments in their fields. With a little grounding in astronomy or physics, the reader will find this book an invaluable source of basic information on the most recent work in this field. Frontiers of Astrophysics can be used as classroom reading, either as a main text or as supplementary reading in astronomy or physics courses, and it can be read with profit by anyone who wants current knowledge presented without complex mathematical arguments. Published within months after the contributions were written, this book is the most convenient and contemporary source on these topics: formation of the solar system (W.R. Ward); new developments in solar research (R. W. Noyes); early phases of stellar evolution (S.E. Storm); endpoints of stellar evolution (A.G.W. Cameron); neutron stars, black holes and supernocvae (H. Gursky); infrared astronomy (G.G. Fazio); gaseous nebulae and their interstellar environment (E.K. Chaisson); chemistry of the interstellar medium (A. Dalgarno); radio observations of galactic masers (J.M. Moran): active galaxies (K. Brecher); galaxies and cosmology (M. Davis); the mass of the universe and intergalactic matter (G.B. Field).