Astronomy Methods: A Physical Approach to Astronomical Observations , Hale Bradt Cambridge U. Press, New York, 2004. $120.00, $65.00 paper (433 pp.). ISBN 0-521-36440-X, ISBN 0-521-53551-4 paper
In the past decade, astronomy and astrophysics have undergone developments of fundamental significance. The increased activity in astrophysics and the field’s strong coupling with other areas of physics have led to the subject’s rising popularity in recent years. This growing interest has resulted in a proliferation of books dealing with theoretical astrophysics at different levels for different kinds of audiences. Neb Duric, once a longtime faculty member at the University of New Mexico’s physics and astronomy department before recently moving to Wayne State University’s medical school in Michigan, adds to this increasing collection with his latest book, Advanced Astrophysics.
Because astronomy is a field of science driven by observations, one of the main objectives of astronomy instructors is to acquaint students with the techniques behind astronomical observations. That is done routinely in good graduate schools, and one would have thought the market would be flooded with books on observational astronomy. Surprisingly, that is not the case. Astronomy Methods: A Physical Approach to Astronomical Observations by Hale Bradt, a professor emeritus in MIT’s physics department, is a wonderful welcome to a field in desperate need of more textbooks covering the subject.
Advanced Astrophysics claims to cover the field in a short span of about 290 pages. I personally believe such a task is impossible if one aims for complete coverage of the subject at a reasonable level. Yet Duric has bravely attempted the impossible, and the result is rather disappointing: If readers do not know the subject, they will find the discussions inadequate; if they are fairly familiar with the subject, they will find the discussions to be of little value.
The problem is further aggravated by the author’s experimenting with a somewhat unconventional structuring of the chapters. His idea, as emphasized in the preface, is to start with a physics topic and describe applications of that topic in different areas of astronomy and astrophysics. Thus, part 1 of the book treats cosmic expansion and large-scale structure as a part of classical mechanics. The thermal history of the universe comes later in part 2 after statistical mechanics has been introduced. It became obvious to me that Duric’s approach leads to a very fragmented view of physics and, to a lesser extent, astrophysics. I was amused to see that a section in part 2 deals with barrier penetration in quantum mechanics while, much later in the book, part 4 is titled “Quantum Mechanics.” Stellar structure is also discussed in part 2, while radiation from accelerated charges and radiative processes are mentioned later, in part 3 and beyond. A better reordering of the topics would be to cover the necessary physics background first and then apply the physics to astrophysical phenomena.
Another shortcoming of the book is that it has no exercises for students to test their understanding. The lack of exercise problems can be a major setback for students. I also did not find any innovative or insightful discussions of conventional topics. Rather, virtually every topic is presented in the familiar manner of several other conventional textbooks. The figures are inadequate and often redundant. For example, I cannot understand why one needs figures 6.1 or 8.3—nothing is conveyed by them that cannot be stated simply in the text. Omitting some of the figures would have given more space for the author to discuss concepts in greater detail. Altogether, I found Advanced Astrophysics to be rather disappointing, especially since several other excellent textbooks deal with the same subject.
Although a fair number of good treatises on theoretical astrophysics exist, there are very few good textbooks on observational astronomy for graduate instruction. One notable exception for several years was the second, revised edition of Observational Astrophysics (Springer-Verlag, 1988) by Pierre Léna, François Lebrun, and François Mignard. But students can certainly do with many more textbooks at that level. Bradt’s Astronomy Methods is a brilliant addition to the pedagogy. It is timely, focused, well written, and at the appropriate level, which makes it an invaluable contribution to the field.
I found several features of the book particularly attractive. First, it is eminently student oriented and suitable for self-study. Each chapter begins with a brief summary in a box explaining what the student can expect to learn, and each chapter concludes with several problems that have been compiled with care. The discussions are kept at an elementary level throughout, and the illustrations are well done and adequately supplement the discussion. In addition to covering the conventional topics one expects in such a book, the author devotes three final chapters to neutrino astrophysics, cosmic-ray physics, and aspects of gravitational-wave observatories.
Bradt provides very insightful coverage of conventional topics. For example, the absorption and scattering of photons in different contexts are illustrated nicely with appropriate diagrams, and issues that are usually confusing to a beginner are clarified with care. I also found that the author actually made the subject of celestial motions and timekeeping quite interesting, a task I thought was virtually impossible! The theoretical descriptions are adequate but are necessarily kept to a minimum. I would have been happier to see a little more theory sprinkled throughout the book or presented in the form of additional problems, but I gather from the preface that a more theoretical volume is under preparation by the author.
In summary, Astronomy Methods will be useful to all students of astronomy and astrophysics, irrespective of whether they intend to specialize in observational astronomy. The material can be adapted easily for various related courses, which makes the book even more valuable.
