Nuclear tracks

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REVIEWS

Lightning, Auroras, Nocturnal Lights, and Related L m i n o u s Phenomena. William R. Corliss. Sourcebook Project, Glen A r m , M d , 1982. 242 pp., $11.95 O v e r the last decade, William R. C o r h s s has a s s e m bled and p u b h s h e d an e x t e n s i v e collection o f a c c o u n t s o f scientific a n o m a h e s . Of special interest to readers of this Journal are two of his more recent volumes, The

Mysterious Umverse" A Handbook o f Astronomical Anomalies (1979)--reviewed in Icarus 41, 4 7 0 - - a n d Unknown Earth A Handbook o f Geologwal Enigmas (1980, 833 pp.). To compile this material, M r Corhss has sifted through what m u s t have been m a n y tons of scientific journals and semipopular works to find and extract primary source a c c o u n t s of unexplained natural p h e n o m e n a , the e s s e n t m l s of which he quotes, with references He aims at objectivity and has done a reasonably good j o b of screening out material from obwously questionable s o u r c e s The present volume, which deals with unexplained l u m i n o u s p h e n o m e n a , is divided into s e v e n major sections: (1) aurora-like p h e n o m e n a , (2) ball hghtnlng, (3) diffuse electrical discharge p h e n o m e n a , (4) lightning anomalies, (5) low-level meteor-like luminous phen o m e n a , (6) nocturnal hghts, and (7) marine phosphorescence. E a c h of these in turn is organized into subsections, for example, the section on diffuse electrical discharge p h e n o m e n a includes mountain-top glows, intermountain electric discharges, large-scale St E i m o ' s fire, e a r t h q u a k e lights, and tornado hghts The section on nocturnal lights includes m a n y good accounts of the will-o'-the-wisp, s o m e t i m e called " s w a m p g a s " but stdl qmte unexplained. Most of the e v e n t s described m this book appear to be puzzling aspects of physical effects which are at least partly u n d e r s t o o d But s o m e others s e e m utterly strange. There is, for example, the class of giant, luminous, rotating pinwheels seen at night on or near the surface o f the s e a (confined apparently to the Indian Ocean, the Arabian Gulf, and the China Sea) Curved lumin o u s spokes, typically s o m e ten meters m width, radiate from a fixed center, In a rotating pattern that sometimes e x t e n d s to the V~slble horizon and often lasts for hours. There are scores of independent observations reported by ships' officers in the last h u n d r e d years The luminosity itself is most likely due to the e x o t a tlon of p h o s p h o r e s c e n t plankton, but what & s t u r b a n c e c a u s e s the beautifully organized moving patterns? The apparent a b s e n c e so far of reports from before the 1870s suggests that propeller-driven ships t h e m s e l v e s m a y have s o m e t h i n g to do with i t - - p e r h a p s interference patterns from acoustic w a v e s echoing off the bottom But if a search o f the literature from the age of sail turns up a n y s u c h a c c o u n t s , we wdl have to think further Does the luminosity of each planktomc protozoan s o m e h o w excite its neighbors with a characteristic p h a s e function such that complex wave patterns can be organized over s u c h a scale 9 Do pairs of intelligent cetaceans a m u s e t h e m s e l v e s by vocally project-

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lng interference patterns upon their o w n p h o s p h o r e s cent " w i d e s c r e e n " a b o v e ? H y d r n p h o n e s and air-craft observations might shed m o r e light on this p h e n o m e non. There is a t e n d e n c y to dismiss the study of such a n o m a l o u s reports as a useless diversion. But I beheve m u c h o f this material warrants an attitude combining skeptical scrutiny with an open mind. A m o n g the phen o m e n a of nature there m u s t be s o m e which occur so infrequently that only an occasional Inadvertent observation is possible. Unfortunately, this niche of freq u e n c y space also provides refuge for a large class of interlopers arising from misperceptlon or imagination or invention. With f r a g m e n t a r y and unreproduclble data, it is often difficult to sort out the genuine natural p h e n o m e n a from the counterfeits. Most scientists understandably do not like to waste their time chasing p h a n t o m s , and c o n s e q u e n t l y the class of genuine a n o m a l o u s p h e n o m e n a remains for the m o s t part unlnvestigated But hidden a m o n g these puzzling accounts are undoubtedly clues to s o m e important scientific discoveries yet to be m a d e Wllham J a m e s recogmzed this w h e n he wrote. " R o u n d about the accredited and orderly facts of every science there ever f o a t s a sort of dust-cloud of exceptional observations, of occurrences minute and irregular and seldom met with, which it always proves m o r e easy to ignore than to attend t o . . a n y o n e will renovate his science who will steadily look after the irregular p h e n o m e n a A n d w h e n the science is renewed, its new formulas often have more o f the voice of the exceptions in them than o f what were s u p p o s e d to be the r u l e s . " Perhaps this overstates the case, but it *s well to r e m e m b e r that sixty years ago the f r a g m e n t a r y evidence for "continental drift" was widely & s m l s s e d as " a n o m a l o u s . " Mr. Corhss has rendered an important service by making accessible m u c h of " t h e unclassified r e s i d u u m " that floats at the periphery of a n u m b e r of s o e n c e s

STEVEN SOTER

Center for Radlophysws and Space Research Cornell Unwerstty Ithaca, New York 14853

Nuclear Tracks. Edited by J. N. Goswami. Indian A c a d e m y of Sciences, 1982 124 pp. $8.00. T h e book is a compilation of s e v e n select papers from a w o r k s h o p on nuclear tracks held in A h m e d a bad, India, 1981. The papers are fairly comprehensive, but c o v e r diverse topics ranging from the origin of low energy cosmic rays to the geochronology of India. Probably the m o s t useful paper in the book is that by G. Poupeau, and it critically e x a m i n e s the a s s u m p t i o n s

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BOOK REVIEWS

and corrections procedures that go into fission track dating studies. Coverage and write-up of the topics involved in the other articles are either average or better reviews already exist elsewhere. For this reason, and the small number of papers included, the book is likely to be hnuted in its usefulness either as a textbook or as a detailed proceedings volume. However, considering the low price, it is a useful reference to have around, at least in the library. SUNDAR RAJAN

Jet Propulsion Laboratory Pasadena, California 91109

Physics of the Jovian Magnetosphere. Edited by A. J. Dessler. Cambridge Univ. Press. New York/ London/Cambridge, 1983, 544 pp , $29.50. This most welcome volume condenses and summanzes current understanding of Jovian magnetosphenc physics in the post-Voyager era. Twelve chapters dealing with the magnetosphere in ItS various manifest a t i o n s - c h a r g e d particles, magnetic fields, plasma waves, electromagnetic emissions--are authored by Voyager investigators, closely associated theoreticlans, and planetary astronomers engaged in complementary ground-based observations While Jupiter, massive and rapidly rotating, and its moons have been studied optically for centuries, its magnetosphere was not discovered until the 1950s, when polarized, strongly nonthermal radio emissions were observed at decameter and decimeter wavelengths and were interpreted in terms of a large planetary magnetic field with an inferred magnetosphere This magnetosphere was observed in sttu by Pioneers 10 and 11 in 1973 and 1974; it was found to indeed be large, measuring at least 50Rj In the solar direction, with its outer radial regions controlled in a highly time variable way by self-contamed plasma, dragged along electrodynamlcally by Jupiter's rapidly rotating magnetic field and confined centrifugally to a disk at low planetary latitudes. Equipped with a new generation of experiments with greater sensitivity and of broader variety than those carried by the exploratory Pioneers, Voyagers 1 and 2 passed through the Jovian magnetosphere in 1979, increased the Jovian data base enormously, unraveled old mysteries, stimulated new ones, and, most importantly, passed close by several of Jupiter's moons, especially enigmatic Io. Three chapters of this book deal with the Jovian magnetospheric plasma separately at low (author, J. W. Belcher), intermediate (S. M. Knmigis and E. C Roelof), and high (A W Schardt and C K Goertz) energies. This plasma, largely sulfur and oxygen in its ionic content, is formed from volcanic effluents emanating from Io and spreads by diffusion and convec-

tion to fill the entire magnetosphere It radiates copiously in the EUV and these emissions, observed by Voyager experiments, and complementary groundbased optical observations are the topic of a chapter authored by R A Brown, C. B Pdcher, and D F Strobel. The plasma also supports a plethora of electromagnetic wave modes whose identification, discussed In a chapter by D. A. Gurnett and F. L. Scarf, has been important also in determining m situ plasma properties. The kinetic theory of these wave modes, with emphasis on the particle scattenngs which they induce, is treated in a separate chapter by R. M Thorne. A chapter by M. H. Acuna, K. W Behannon, and J . E. P. Connerney discusses the magnetic field-of planetary origin near the Jovian surface, distended radially by a plasma-camed ring current in the middle magnetosphere, and ultimately compressed on the dayside and drawn out nightward into a long tail by the solar wind V M Vasyhunas has contributed a chapter in which he analyzes resultant magnetic models from the standpoint of their magnetohydrodynamlc equdibnum Radio observations, both Earth-based and from the Voyager radio astronomy experiments, including newly discovered kllometric components, are reviewed in a chapter by T D Carr, M. D. Desch, and J. K. Alexander Linear and nonlinear plasma theories for the generation of decametnc emissions are summarized in a related chapter by M. L Goldsteln and C. K. Goertz. Structure of the Jovian ionosphere, as inferred from occultation of the radio signal of both the Pioneer and Voyager spacecraft, is the topic treated by D. F Strobel and S. K Atreya. Finally, a chapter by T W Hill, A. J. Dessler, and C. K Goertz treats several observationally motivated topics from a theoretical viewpoint, the adequacy of Io as a plasma source, electrodynamlc couphng of Io to the Jovian ionosphere, particle acceleration processes, and phasing mechanisms for the pervasive 10-hour (planetary) periodicities seen by almost all experiments The order of chapters, as mentioned here, is not the order of presentation, where the eight observatlonally oriented chapters are followed by the four theoretical ones. However, as Editor Dessler states in his preface, "they need not be read in any particular order " One of the satisfactions of Jovian magnetospherlc physics today is that physicists in diverse fields, working with complementary techniques, are achieving frequently compatible results An obvious effort has been made to stress science-with refreshing success. Results are conveyed in an abundance of figures There is not a word about instrumentation or data analysis methods, however, an extensive, common bibliography is appended and the interested reader should have no difficulty finding such information While It IS not a popularization, Physics o f the Joman Magnetosphere is written at a level understandable to the mature physicist and astronomer. Each topic is treated in depth; whatever small criticism may