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Exploration of the universe
654
BOOK REVIEWS
transport does not go significantly beyond the concepts of one-dimensional eddy diffusion and molecular diffusion. However, despite the brevity of these two chapters, the reader gets the essence of cloud physics and atmospheric mixing. The next two chapters, Chapters 5 and 6, on the photochemistry of neutral and ionized species, respectively, constitute the backbone of the book. Chapter 5 reviews the photochemistry of NH3, PH3, CH4, HzS, and a little of the C - N and C - O coupled chemistry. The discussion is fairly complete and includes even an obscure reference o n C6H 6 chemistry reported at a DPS meeting. The emphasis in this chapter is on phenomenology; there is little in-depth treatment of any topic in atmospheric chemistry. Chapter 6 provides an overview of ion chemistry. The subject matter is somewhat less complicated and the treatment adequately covers the recent advances in the field. Related topics such as joule heating, particle precipitation, and thermal balance of the thermosphere have been included. The last chapter, Chapter 7, covers the larger satellites of the outer solar system, with emphasis on 1o and Titan. The extensive observations are summarized in a large number of figures and tables. The chemical composition of the atmospheres of the satellites is not dominated by H2, and consequently exhibits greater variety in coupled chemistry and greater range of oxidation state. This chapter provides good coverage of this diversity as well as origin and evolution of satellite atmospheres. The formula for estimating the maximum flux of hydrogen from Titan on p. 178 (7.11) is improperly used because there is CH4 photolysis above the homopause. The flux actually computed in a detailed model is many times that estimated using the author's simple formula. In summary, this is a useful little book on the atmospheres of the outer solar system. It contains a comprehensive summary of recent spacecraft data. It is brief and readable and should be a standard reference for anyone interested in the outer solar system. YuK L. YUNG
Geological and Planetary Sciences California Institute of Technology Pasadena, California 91125
The Sun and Solar System Debris, A Catalog of Astronomical Anomalies. William R. Corliss. The Sourcebook Project, P.O. Box 107, Glen Arm, MD 21057. 1986. 282 pp., $17.95. Corliss collects anomalies and this is the twenty-first book that he has published on them. In the preface he exclaims that anomalies abound: "Nature is very anomalous or, equivalently, Nature is not yet wellunderstood by science." In this catalog of anomalies,
each one is given a description, its background is presented, the data and the degree of anomaly are evaluated, and a possible explanation is offered, and similar or related phenomena are also given. It seems impossible for one person to assess so many anomalies in our observable universe, but Corliss does remarkably well in this book. He does not seem to have a system of refereeing or asking expert opinions; I like that because some of the reports would have been eliminated as "nonsense," There is merit in the complete listing, with only Corliss' selection, and then leaving it to the reader to decide and possibly investigate. I do have a few detailed comments in looking through the book. The Chiron orbit does not seem elliptical enough, references are rather from popular sources, Nemesis would have been too slow for Tombaugh to have discovered in his blinking of plates, and so many passages seen across the Sun seem to be useless to report. But at least they make us more aware of the possibility of such passages, also across Jupiter, and it makes me for one a more attentive observer. 1 was not aware of the fact that the splitting of cometary nuclei occurs mostly for new ones, and mostly near the plane of the ecliptic; the two facts seem contradictory, which yields another challenge. It is an unusual book, nicely executed, and I recommend it highly as fun to peruse while it will give ideas for investigation and for keeping our senses alert. T. GEHRELS
Lunar and Planetary Laboratory University of Arizona Tucson, Arizona 85721
Exploration of the Universe, 5th ed. By George O. Abell, David Morrison, and Sidney C. Wolff. Saunders, Philadelphia, 1987. 748 pp., $34.25. Astronomy, for a variety of reasons, has always held a broad appeal for college students, both science majors as well as those faced with a science requirement in a liberal arts or humanities curriculum. This appeal has only strengthened in the last 2 decades with the successes of the (currently phlegmatic) U.S. space program and the dissemination of new, exciting discoveries through the popular media. Astronomy survey classes are now even in more demand and in the past decade the textbook industry has kept pace with a wide variety of lavishly illustrated up-to-date astronomy texts. Moreover, these books are revised every few years in order to keep pace with new developments (and presumably to ensure a higher return for the authors and publishers). Thus, it is with anticipation that the current revision of the classic text Exploration of the Universe, by the
BOOK REVIEWS late George Abell, was received. The large task of bringing the book up-to-date was done by Sidney Wolff and David Morrison and they have succeeded in making it thoroughly contemporary while retaining the basic integrity and comprehensiveness of the original (I have, in fact, compared it only to the third edition of 1974). Moreover, they have done so without cluttering the pages with additional, often superfluous, material in the form of texts in margins, sidebars, or "guest comments" that seem to be in vogue these days. The only basic change in style from the earlier edition is the use of a smaller typeface for sections deemed "amplifying and mathematical" and the inclusion next to each chapter heading of a photograph (or painting reproduction) of a prominent scientist who played a major role in the development of the subject of that chapter. The primary audience for this book is the beginning science student. The book is too comprehensive and detailed (even omitting the designated "amplifying" sections) to serve as the basis for a one-semester survey course for nonseience majors. Like most similar texts, the book divides naturally into three sections: astronomical measurements and underlying physical principles; the Solar System; and stars, galaxies, and cosmology, and can be easily used for single-semester introductory courses in either planetary astronomy or stellar and galactic astronomy. To cover the full text requires two semesters. The chapters on the Solar System, as revised by Morrison, include images and results of the 1986 planetary encounters (Uranus and comet Halley) as well as discussion of current interpretations of the large body of data accumulated in 2 decades of lunar and planetary exploration. Needless to say, most of this material has been completely rewritten, and the inclusion of con-
655
troversial and thought-provoking subjects, such as the extinction of the dinosaurs, only enlivens what is otherwise a thorough overview of the current status of planetary science. Most welcome is the final chapter of the book which concisely addresses the questions of life in the universe and the search for other planetary systems. Placed at the end of the book, this chapter, more so than the penultimate chapter on big bang cosmology, serves to put the entire subject of astronomy into its proper context in Western civilization. One hopes that it is not excised in actual course use because of time limitations. The remainder of the text appears to have been revised with equal care. Of special merit to my mind are the chapters on observational techniques spanning the electromagnetic spectrum from radio to X- and gamma-rays, as well as material on the new technology optical telescopes. After all, the readers are presumably the future taxpayers who are going to be called on to support these planned space and groundbased initiatives. No book of this type is perfect and I did find a few debits in my random reading of the 690 pages of text. The discussion of tides, carried over from the earlier edition, is both turgid and inadequate. On page 330, James Van Allen is associated with the wrong university in Iowa. These are minor comments on what appears to be an excellent revision and a worthy successor to the earlier editions of Exploration of the
Universe. PAUL D. FELDMAN
Department of Physics & Astronomy Johns Hopkins University Baltimore, Ma~. land 21218
BOOK REVIEWS
transport does not go significantly beyond the concepts of one-dimensional eddy diffusion and molecular diffusion. However, despite the brevity of these two chapters, the reader gets the essence of cloud physics and atmospheric mixing. The next two chapters, Chapters 5 and 6, on the photochemistry of neutral and ionized species, respectively, constitute the backbone of the book. Chapter 5 reviews the photochemistry of NH3, PH3, CH4, HzS, and a little of the C - N and C - O coupled chemistry. The discussion is fairly complete and includes even an obscure reference o n C6H 6 chemistry reported at a DPS meeting. The emphasis in this chapter is on phenomenology; there is little in-depth treatment of any topic in atmospheric chemistry. Chapter 6 provides an overview of ion chemistry. The subject matter is somewhat less complicated and the treatment adequately covers the recent advances in the field. Related topics such as joule heating, particle precipitation, and thermal balance of the thermosphere have been included. The last chapter, Chapter 7, covers the larger satellites of the outer solar system, with emphasis on 1o and Titan. The extensive observations are summarized in a large number of figures and tables. The chemical composition of the atmospheres of the satellites is not dominated by H2, and consequently exhibits greater variety in coupled chemistry and greater range of oxidation state. This chapter provides good coverage of this diversity as well as origin and evolution of satellite atmospheres. The formula for estimating the maximum flux of hydrogen from Titan on p. 178 (7.11) is improperly used because there is CH4 photolysis above the homopause. The flux actually computed in a detailed model is many times that estimated using the author's simple formula. In summary, this is a useful little book on the atmospheres of the outer solar system. It contains a comprehensive summary of recent spacecraft data. It is brief and readable and should be a standard reference for anyone interested in the outer solar system. YuK L. YUNG
Geological and Planetary Sciences California Institute of Technology Pasadena, California 91125
The Sun and Solar System Debris, A Catalog of Astronomical Anomalies. William R. Corliss. The Sourcebook Project, P.O. Box 107, Glen Arm, MD 21057. 1986. 282 pp., $17.95. Corliss collects anomalies and this is the twenty-first book that he has published on them. In the preface he exclaims that anomalies abound: "Nature is very anomalous or, equivalently, Nature is not yet wellunderstood by science." In this catalog of anomalies,
each one is given a description, its background is presented, the data and the degree of anomaly are evaluated, and a possible explanation is offered, and similar or related phenomena are also given. It seems impossible for one person to assess so many anomalies in our observable universe, but Corliss does remarkably well in this book. He does not seem to have a system of refereeing or asking expert opinions; I like that because some of the reports would have been eliminated as "nonsense," There is merit in the complete listing, with only Corliss' selection, and then leaving it to the reader to decide and possibly investigate. I do have a few detailed comments in looking through the book. The Chiron orbit does not seem elliptical enough, references are rather from popular sources, Nemesis would have been too slow for Tombaugh to have discovered in his blinking of plates, and so many passages seen across the Sun seem to be useless to report. But at least they make us more aware of the possibility of such passages, also across Jupiter, and it makes me for one a more attentive observer. 1 was not aware of the fact that the splitting of cometary nuclei occurs mostly for new ones, and mostly near the plane of the ecliptic; the two facts seem contradictory, which yields another challenge. It is an unusual book, nicely executed, and I recommend it highly as fun to peruse while it will give ideas for investigation and for keeping our senses alert. T. GEHRELS
Lunar and Planetary Laboratory University of Arizona Tucson, Arizona 85721
Exploration of the Universe, 5th ed. By George O. Abell, David Morrison, and Sidney C. Wolff. Saunders, Philadelphia, 1987. 748 pp., $34.25. Astronomy, for a variety of reasons, has always held a broad appeal for college students, both science majors as well as those faced with a science requirement in a liberal arts or humanities curriculum. This appeal has only strengthened in the last 2 decades with the successes of the (currently phlegmatic) U.S. space program and the dissemination of new, exciting discoveries through the popular media. Astronomy survey classes are now even in more demand and in the past decade the textbook industry has kept pace with a wide variety of lavishly illustrated up-to-date astronomy texts. Moreover, these books are revised every few years in order to keep pace with new developments (and presumably to ensure a higher return for the authors and publishers). Thus, it is with anticipation that the current revision of the classic text Exploration of the Universe, by the
BOOK REVIEWS late George Abell, was received. The large task of bringing the book up-to-date was done by Sidney Wolff and David Morrison and they have succeeded in making it thoroughly contemporary while retaining the basic integrity and comprehensiveness of the original (I have, in fact, compared it only to the third edition of 1974). Moreover, they have done so without cluttering the pages with additional, often superfluous, material in the form of texts in margins, sidebars, or "guest comments" that seem to be in vogue these days. The only basic change in style from the earlier edition is the use of a smaller typeface for sections deemed "amplifying and mathematical" and the inclusion next to each chapter heading of a photograph (or painting reproduction) of a prominent scientist who played a major role in the development of the subject of that chapter. The primary audience for this book is the beginning science student. The book is too comprehensive and detailed (even omitting the designated "amplifying" sections) to serve as the basis for a one-semester survey course for nonseience majors. Like most similar texts, the book divides naturally into three sections: astronomical measurements and underlying physical principles; the Solar System; and stars, galaxies, and cosmology, and can be easily used for single-semester introductory courses in either planetary astronomy or stellar and galactic astronomy. To cover the full text requires two semesters. The chapters on the Solar System, as revised by Morrison, include images and results of the 1986 planetary encounters (Uranus and comet Halley) as well as discussion of current interpretations of the large body of data accumulated in 2 decades of lunar and planetary exploration. Needless to say, most of this material has been completely rewritten, and the inclusion of con-
655
troversial and thought-provoking subjects, such as the extinction of the dinosaurs, only enlivens what is otherwise a thorough overview of the current status of planetary science. Most welcome is the final chapter of the book which concisely addresses the questions of life in the universe and the search for other planetary systems. Placed at the end of the book, this chapter, more so than the penultimate chapter on big bang cosmology, serves to put the entire subject of astronomy into its proper context in Western civilization. One hopes that it is not excised in actual course use because of time limitations. The remainder of the text appears to have been revised with equal care. Of special merit to my mind are the chapters on observational techniques spanning the electromagnetic spectrum from radio to X- and gamma-rays, as well as material on the new technology optical telescopes. After all, the readers are presumably the future taxpayers who are going to be called on to support these planned space and groundbased initiatives. No book of this type is perfect and I did find a few debits in my random reading of the 690 pages of text. The discussion of tides, carried over from the earlier edition, is both turgid and inadequate. On page 330, James Van Allen is associated with the wrong university in Iowa. These are minor comments on what appears to be an excellent revision and a worthy successor to the earlier editions of Exploration of the
Universe. PAUL D. FELDMAN
Department of Physics & Astronomy Johns Hopkins University Baltimore, Ma~. land 21218