"I would warmly recommend the book to a good graduate student of astronomy who is preparing for general exams, or to a graduate student working in particle physics who is shifting to the astroparticle side. The text could also serve as a focus for an inspirational graduate seminar that would broaden and deepen students' understanding of physics and the way it enables us to understand environments wildly unlike our own ... It is an unconventional but very worthwhile book."Physics Today"This book is a nice introduction to several fields of astrophysics. It is useful for students interested in this special field, but also for researchers of several other fields, as it concentrates on the fundamental questions instead of going into too much details."Zentralblatt MATH"A welcome aspect of this book is the inclusion of many thoughtful problems at the end of each chapter ... The interested student will learn a great deal by tackling these problems."American Journal of Physics