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asteroidal, meteoritic, and planetary formation are addressed. What were the heating mechanisms on the asteroid parent bodies? Where did the asteroids and meteorites originate? Why have we not found an asteroid with a spectrum that matches that of the ordinary chondrites, a meteorite class encompassing 70% of our samples? The final article is another installment in the continuing saga of the formation of the solar system according to Cameron. To complete this impressive collection, Gehrels and several of his authors have assembled the entire Tucson Revised Index of Asteroid Data (TRIAD), a systematic compilation of the observational characteristics of the asteroids. Although available as well in machine-readable form, this tabulation will undoubtedly be of great value to asteroid researchers. Although this book is not without its flaws--some of the articles, for example, would have benefited from a sterner editorial hand--it is sure to become one of the standard references in planetary science. A good index and glossary, and copious cross-references make it easy to use (an important characteristic of a volume of almost 1200 pages). For both planetary scientists and others interested in the field, this book is an informational resource that will set the standard for other source books to be published in coming years. C. B. PILCHER

Institute for Astronomy, University o f Hawaii, Honolulu, Hawaii 96822 Solar System Plasma Physics, Vols. I-lII. Edited by C. F. Kennel, L. J. Lanzerotti, and E. N. Parker. North-Holland, Amsterdam, 1979. A United States National Academy of Sciences report issued in 1978 concluded that "space plasma physics is intrinsically an important branch of science." This three-volume series is an excellent testimony to that conclusion. The volumes can be read in whole or in part and the many fine papers cover most aspects of solar system plasma physics through 1977. These volumes also do a remarkable job in celebrating the twentieth anniversary of space research by presenting a picture of the solar system and planetary environments which contains major modifications from what would have been presented a quarter century ago. For example, the vacuum of outer space has been replaced by a high-velocity, collisionless plasma flowing out from the Sun--the solar wind. Further, the interaction of the solar wind with planetary bodies produces at each planet an extensive environment of turbulent plasmas and energetic particles--the planetary magnetosphere. The authors consider these modifications--from the expulsion of plasma from the Sun through its propagation within the solar system to

its interaction with the planets--and present, in varying detail, the data and theoretical concepts which are guiding the field toward an understanding of the behavior of and interactions between these naturally occurring plasmas. The large variety of boundary conditions found in solar system plasmas will provide productive and exciting research for years to come, and should form the basis of a strong and vigorous graduate student program. The rapid evolution of this field to a quantitative physics program (as distinct from discovery and exploration) may present the reader with a few surprises. Not only are the developing concepts of comparative magnetospheric theory presented, but many examples are given showing the applicability of solar system plasma studies to large-scale astrophysical problems. (We note that a theory of solar system formation and evolution based on plasma physics principles has been developed by Alfv6n and Arrhenius.) The quantitative nature of the papers in these volumes strongly supports the idea of using solar system plasmas as an accessible cosmic laboratory for quantitative astrophysical and cosmological studies. In addition, studies of plasma phenomena (e.g., collisionless shocks, energy transfer between magnetic fields and plasmas, highly efficient wave generation), at best only poorly simulated in the laboratory because of boundary effects, can be successfully conducted in the solar system plasma environment. Volume III presents an additional surprise in its documentation of the sensitivity of society's technological systems to variations in the solar wind, magnetospheric and ionospheric plasma populations, and their interactions. It appears that mankind, with its increasing dependence on high technology, must lift its environmental horizon from the immediate atmosphere to the surface of the Sun. In summary, these volumes present the status of an exciting and productive field of quantitative scientific research, convey its applicability to astrophysical studies and laboratory plasma physics, and show the potential of innovative and direct practical benefits to mankind. They will provide an excellent reference text for graduate students, researchers in the field, and researchers in allied fields such as laboratory plasma physics and astrophysics. D. J. WILLIAMS

NOAA Space Environment Laboratory Boulder, Colorado 80303

Planetary Geology. John Guest with Paul Butterworth, John Murray, and William O'Donnell. Halsted Press, New York, 208 pp. My first reaction from viewing the dust cover of this book, which is solemnly embellished with the stark

BOOK photograph of a deeply s h a d o w e d impact crater, was to get prepared for s o m e really h e a v y reading. The second impression, gained from a c u r s o r y flip through the pages, which are paired as glossy pictures on the right and text on the left, w a s o f a coffee table picture book directed toward a lay audience. This delightful little book by the English planetary geologist and his collaborators belies these initial impressions. It is a well-constructed introduction to the geography o f the surfaces o f planets and satellites and to the geological p r o c e s s e s that have created their landforms. Wearing their learning exceedingly lightly, the a u t h o r s s h o w how a detailed picture of planetary surface evolution can be erected largely on the basis of methodical analysis of photographs. U n b u r d e n e d by technical jargon and uncluttered by p o n d e r o u s references to the literature, the book vividly c o n v e y s h o w planetary imaging has also s p a w n e d a host o f questions about the evolution o f planetary interiors. The longest stretch o f text appears in the introduction where the a u t h o r s discuss the impact o f planetary science and a s t r o n o m y on the older earth science o f geology. T h e y suggest that the global view of terrestrial geology based on plate tectonics has been stimulated by global views of the planets provided by spacecraft imaging. T h e y also contend that a s t r o n o m y has influenced the attitudes o f terrestrial geologists w h o are now comfortable with exotic topics s u c h as planetary accretion and differentiation, whereas, previously their " f e a r o f things cosmological" ruled out such alien concepts. Continuing in a philosophical vein, the a u t h o r s r e a s s e s s the uniformitarian and catastrophist approaches to the study o f the Earth and planets• T h e y contend that the uniformitarian approach s u m m a r i z e d in the epigram " t h e present is the key to the p a s t " has worked well for the past 600 million years o f the E a r t h ' s history during which time p r o c e s s e s have not differed a great deal from those of today. However, they suggest that in order to unravel the e v e n t s o f earlier periods, geologic history for the Earth as well as the planets is best viewed as a series o f catastrophies evolving in a unidirectional way with time. As far as its t r e a t m e n t o f the planets is concerned, the book is admirably balanced. I shall resist the temptation to follow T h o m a s Mutch, who published a complex bar chart in these pages three years ago to illustrate the mix o f subject matter in a n o t h e r text on planetary geology, and only describe briefly how space is allocated: M o o n - - 5 0 pages; M e r c u r y - - 3 6 pages; Mars (including Phobos and D e i m o s ) - - 9 2 pages; V e n u s - - 4 pages; and the Galilean satellites---6 pages• Obviously, the Moon, Mercury, and Mars represent

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the core of the book. T h e Moon is used as the basis for discussing basic planetary surface p r o c e s s e s s u c h as impact cratering, basin formation, vulcanism, and t e c t o n i s m and stratigraphic m e t h o d s in photogeology. Mercury is then introduced and contrasted with the Moon in respect to the c o n s e q u e n c e s o f these processes, and finally Mars, with its rich variety o f surface types, gets a thorough treatment. By using Mercury as the link between the Moon and Mars, the a u t h o r s are able to establish s o m e relevance and interest in this geologically poorly e n d o w e d body. Although, generally oriented to an American audience in style and perspective, s o m e c h a r m i n g idiosyncracies occasionally creep in. Some are strictly British, such as the reference to U.S. a s t r o n o m e r A s a p h Hall's successful search for Martian satellites: " T h e s e he n a m e d respectively Deimos (Terror) and Phobos (Fear) after the two s o n s o f a t t e n d e n t s o f the god Mars • . . although perhaps Hall should have n a m e d one after his wife who reputedly revived his flagging spirits, no doubt with a cup t~f tea, after a long and initially fruitless s e a r c h . " Elsewhere the history o f scientific discovery is seen from a European perspective when the authors state that: " S t u d i e s o f the rate of m o v e m e n t of surface markings enabled a s t r o n o m e r s to calculate that Mercury rotates exactly three times while circling the Sun twice, giving it a day which is two of its Earth years l o n g , " ignoring the American role in the discovery of M e r c u r y ' s rotation period with the definitive radar observations from Arecibo in 1965. This c h a p t e r would also have been enriched by a discussion of the recognition and explanation of the Mercury spin-orbit r e s o n a n c e which took place immediately after the Arecibo discovery and o f the influence of tidal despinning on Mercurian tectonics which w a s stimulated by Mariner 10 photographs. T h e r e are few errors in the text. The channel closest to the Viking I landing site is incorrectly identified as Kasei instead o f Maja. The crater Timocharis turns upside down b e t w e e n its appearance on the dust cover and the reproduction o f the identical photograph in the text. But t h e s e are minor things. This is, in s u m m a r y , an excellent book to learn s o m e t h i n g about planetary surfaces and the way the photogeologist studies them. It belongs on the bookshelf o f e v e r y student o f planets and is a valuable s u p p l e m e n t a r y text to a course in planetary science• JAMES A. CUTTS Planetary Science Institute Science Applications Inc. Pasadena, California 91101