What role does viscosity play in accretion discs? How do you calculate the 'glitch function' of a pulsar? And can strong shocks account for the energy spectrum of electrons in our Galaxy? These are just some of the exciting questions that Professor Longair uses to develop the physics needed by the astronomer and high energy astrophysicist. The highly acclaimed first edition of High Energy Astrophysics instantly established itself as a classic in the teaching of contemporary astronomy. Reflecting the immense interest and developments in the subject, Professor Longair has developed the second edition into three texts; in this second volume he provides a comprehensive discussion of the high energy astrophysics of stars, the Galaxy and the interstellar medium. He develops an understanding for the essential physics with an elegance and infectious enthusiasm for which his teaching is internationally renowned, illustrating the issues throughout with results from forefront research. This book takes the student with a knowledge of physics and mathematics at the undergraduate level - but not necessarily with training in astronomy - to the point where current astronomical research can be understood.