This volume, published in honor of Prof. Luigi Crocco, appears when Luigi Crocco celebrates his 75th birthday of a life devoted to study, research, and teaching. The events in his life and World War II forced Luigi Crocco, as well as other Italian scientists, to look to foreign countries for the calm haven so vital to study. This notwithstanding, his scientific activity was never inter rupted, and this volume is an acknowledgment of scientists and researchers to his work and life. Prefazione Questo volume in onore del prof. ing. Luigi Crocco vede la luce quando Luigi Crocco compie i 75 anni di una vita dedicata allo studio, alia ricerca e all'insegnamento. a Le vicende della vita, ed anche della 2 guerra mondiale, hanno costretto Luigi Crocco, come altri scienziati italiani, a dover cercare in altri Paesi quella serenita necessaria per dedicarsi allo studio. Ma la sua attivita scientifica non ha avuto interruzioni e questo volume essere la testimonianza di studiosi e di ricercatori alia sua opera e alia sua vita."

Studying the complex physical systems of stellar jets necessitates the incorporation of nonlinear effects which occur on a wide variety of length and timescales. One of the primary methods used to study the physics of jets is numerical simulations that apply high performance computing techniques. Such techniques are also required for analysing the huge modern astrophysical datasets. This book examines those computing techniques. It is a collection of the lectures from the fifth and final school of the JETSET network, "Jets From Young Stars V: High Performance Computing in Astrophysics." It begins with an introduction to parallel programming techniques, with an emphasis on Message Passing Interface (MPI), before it goes on to review grid technology techniques and offer a practical introduction to Virtual Observatory. The second half of the book, then, is devoted to applications of high performance computing techniques, including 3D radiation transfer, to jet and star formation processes. Aimed at graduate students in astrophysics, this book presents state-of-the-art methods, thereby offering interesting new insights to researchers in the field.

Astronomical jets are key astrophysical phenomena observed in gamma-ray bursts, active galactic nuclei or young stars. Research on them has largely occurred within the domains of astronomical observations, astrophysical modeling and numerical simulations, but the recent advent of high energy density facilities has added experimental control to jet studies. Front-line research on jet launching and collimation requires a highly interdisciplinary approach and an elevated level of sophistication. Bridging the gaps between pure magnetohydrodynamics, thermo-chemical evolution, high angular resolution spectro-imaging and laboratory experiments is no small matter. This volume strives to bridge those very gaps. It offers a series of lectures which, taken as whole, act as a thorough reference for the foundations of this discipline. These lectures address the following: * laboratory jets physics from laser and z-pinch plasma experiments, * the magnetohydrodynamic theory of relativistic and non-relativistic stationary jets, * heating mechanisms in magnetohydrodynamic jets, from the solar magnetic reconnection to the molecular shock heating perspectives, * atomic and molecular microphysics of jet shocked material. In addition to the lectures, the book offers, in closing, a presentation of a series of observational diagnostics, thus allowing for the recovery of basic physical quantities from jet emission lines.

Physics of the Inner Heliosphere gives for the first time a comprehensive and complete summary of our knowledge of the inner solar system. Using data collected over more than 11 years by the HELIOS twin solar probes, one of the most successful ventures in unmanned space exploration, the authors have compiled six extensive reviews of the physical processes of the inner heliosphere and their relation to the solar atmosphere. Researchers and advanced students in space and plasma physics, astronomy, and solar physics will be surprised to see just how closely the heliosphere is tied to, and how sensitively it depends on, the sun. Volume 2 deals with particles, waves, and turbulence, with chapters on: - magnetic clouds - interplanetary clouds - the solar wind plasma and MHD turbulence - waves and instabilities - energetic particles in the inner solar system

The 1985/86 apparition of Halley's Comet turned out to be the most important apparition of a comet ever. It provided a worldwide science community with a wealth of exciting new discoveries, the most remarkable of which was undoubtedly the first image of a cometary nucleus. Halley's Comet is the brightest periodic comet, and the most famous of the 750 known comets. With its 76-year period, its recent appearance was truly a "once-in-a-lifetime" observational opportunity. The 1985/86 apparition was the thirtieth consecutive recorded apparition. Five apparitions ago, the English astronomer Edmond Halley discovered the periodicity of "his" comet and correctly predicted its return in 1758, a triumph for science best appreciated in the context of contemporary views, or rather fears, about comets at that time. The increasingly rapid progress in technological development is very much apparent when one compares the dominant tools for cometary research during Halley's next three apparitions: in 1835 studies were made based on drawings ofthe comet; in 1910 photographic plates were used; while in March 1986 an armada of six spacecraft from four space agencies approached the comet and carried out in situ measurements, 1 AU from the Earth. In 1910, nobody could have dreamed that this was possible, and today it is equally difficult to anticipate what scientists will be able to achieve in 2061.

This monograph is concerned with the fundamentals of up-to-date geo metrical optics treated as an approximate method of wave theory. Geometrical optics has changed dramatically over the last two decades. Primarily, it has acquired a number of novel disciplines: space-time geo metrical optics, the quasi-isotropic approximation, the modern theory of caustics related to catastrophe theory, and perturbation techniques for rays, to name only a few. Another acquisition is the reliable boundaries of appli cability for geometrical optics, based upon the concept of the Fresnel volume for a ray. These recent additions to the field are the focus of dis cussion in the book. We did not attempt to separate study-oriented and illustrative material from that intended for professionals, but rather we spread it throughout the text to facilitate for the reader the mastering of this attractive, intuitively appealing and efficient ray method. In preparing the manuscript we used a set of lecture notes devised for All-Union Schools on Diffraction and Wave Propagation, published in Rus sian. Sections 2.1-4,6 and 10 result from joint efforts of both authors. The other material of the book we wrote separately. I contributed Sects. 2.5,9 and 3.17 and Chap.4; Yu.l. Orlov prepared the rest. Unfortunately, he could not take part in the preparation of the English edition, as he died in 1982 at the age of 41, on the verge of what would have been great achieve ments considering his strong and original talent."

The aim of this book is to describe contemporary analytical and semi analytical techniques for solving typical celestial-mechanics problems. The word "techniques" is used here as a term intermediate between "methods" and "recipes." One often conceives some method of solution of a problem as a general mathematical tool, while not taking much care with its computa tional realization. On the other hand, the word "recipes" may nowadays be understood in the sense of the well-known book Numerical Recipes (Press et al., 1992), where it means both algorithms and their specific program realiza tion in Fortran, C or Pascal. Analytical recipes imply the use of some general or specialized computer algebra system (CAS). The number of different CAS currently employed in celestial mechanics is too large to specify just a few of the most preferable systems. Besides, it seems reasonable not to mix the essence of any algorithm with its particular program implementation. For these reasons, the analytical techniques of this book are to be regarded as algorithms to be implemented in different ways depending on the hardware and software available. The book was preceded by Analytical Algorithms of Celestial Mechanics by the same author, published in Russian in 1980. In spite of there being much common between these books, the present one is in fact a new mono graph."

The International Astronautical Federation is the only professional society in the field of aerospace engineering and Sciences which brings together specialists of all countries interested in the exploration and peaceful exploitation of space. At its annual Congresses a large number of invited and/or carefully selected con tributed papers are presented which cover a wide variety of topics and are distributed over a number of sessions, each one being organized by two leading scientists who later chair the session itself. Each year the selection of specific topics to be dealt with. is dictated either by significant new progress achieved in some sectors or by new developments and trends which are liable to influence substantially the objectives toward which space research and/or application of space technology will be oriented in the immediate future. A second rigorous screening, performed with the help of the Session Chairmen and carried out according to the same criteria identifies finally the papers which are published in the Proceedings. The outcome of all this is reliable and authoritative information as to the actual status and future trends of space activities, both from the research point of view and from the point of view of u ilization and/or application."

t~icrogravity research, a new field originating from the accessibility of space, has reached the age of adolescence. An impressive set of results has emerged from the fi rst Space 1 ab fl i ght, whi ch by now has been fully evaluated. In view of this and the wealth of information available from other space experiments, ground based research, and short-term microgra- vity experiments in ai rp 1 anes, rockets or fall towers, it was felt that the time was ripe for a comprehensive review of the field. The initiative of the US to build a permanent station in space, which was soon followed by a European decision to join this venture, further focussed attention onto microgravity materials sciences. This originates from the interesting prospects of a commercial space uti 1 ization, which would heavily rely on the results of scientific or technical experiments in space. From this point of view it also seemed timely and essential to provi de prospective commerci a 1 users with the necessary i nformat i on on previous experience, and more importantly, with a sound scientific basis for space processing. The aim of the present volume consequently is twofold, namely - to stimulate new scientific experiments in space in order to expand our knowledge gained from microgravity research, and to provide industry with the information obtained from space experi- ments sofar and to contribute to the scientific background for commer- cial space utilization.

The analysis and computational techniques associated with the navigation and guidance of spacecraft are now in a mature state of development. However the documentation has remained dispersed throughout conference papers, journals, company and contract rep orts, making it difficult to get a true, comprehensive picture of the subject. This text brings together the body of literature with suitable attention to the necessary underlying mathematics and computational techniques. It covers in detail the necessary orbital mechanics, orbit determination with emphasis on the SRIF algorithm, gr avity assist manoeuvres and guidance, both ground-based and autonomous. Attention is paid to all phases of a space mission including launch and re-entry, and whether culminating in an earth satellite or a deep space mission to planets or primitive bodies. Software associated with the text is available free to the reader by means of the Internet server of the publisher. 'Spacecraft Navigation and Guidance' is an invaluable aid for all those working within astronautics, aeronautics, and control engineering in general.

The experimental study of magnetospheric processes consists of several disci plines or methods, developing in two general directions. The first, internal trend covers the progress in experimental techniques and methods and re search specific to this discipline. The other trend combines with other methods in a mutual attempt at understanding the boiling whirlpool of the disturbed magnetosphere. Investigations of auroral X-rays began after Van Allen's (1957) discovery of hard radiation in the upper atmosphere of the auroral zone, and are based on high latitude balloon observations. Scientific apparatus, payload equip ment, and particular questions of scientific ballooning are discussed in Chap ter 1. Chapter 2 concludes the internal trend of the subject by describing the problems of X-ray generation at the boundary of the atmosphere and propa gation downward to balloon altitudes. Auroral X-rays are closely related to most of the processes of the disturbed magnetosphere through energetic auroral electrons; precipitating into the at mosphere, the latter create bremsstrahlung photons able to penetrate to an at mospheric depth of 10- 20 g cm - 2. In quiet periods auroral electron flux ex ists only in embryo, as a hot plasma layer at the inner edge of the plasma sheet: in general it is a transient phenomenon caused by magnetospheric distur bances and carrying valuable information of the magnetospheric dynamics."

As this excellent book demonstrates, the study of comets has now reached the fas cinating stage where we understand comets in general simple tenns while, at the same time, we are uncertain about practically all the details of cometary nature, structure, processes, and origin. In every aspect, even including dynamics, a choice among several or many competing theories is made impossible simply by the lack of detailed knowledge. The space missions, snapshot studies of two comets, partic ularly the one that immortalizes the name of Sir Edmund Halley, have produced a huge mass of valuable new infonnation and a number of surprises. Nonetheless, we face the tantalizing realization that we have obtained only a fleeting glance at two of perhaps a hundred billion (lOll) or more comets with possibly differing natures, origins, and physical histories. To my personal satisfaction, comets seem to have discrete nuclei made up of dirty snowballs, as I concluded four decades ago, but perhaps they are more like frozen rubbish piles.

Lectures on Non-linear Plasma Kinetics is an introduction to modern non-linear plasma physics showing how many of the techniques of modern non-linear physics find applications in plasma physics and how, in turn, the results of this research find applications in astrophysics. Emphasis is given to explaining the physics of nonlinear processes and the radical change of cross-sections by collective effects. The author discusses new nonlinear phenomena involving the excitation of coherent nonlinear structures and the dynamics of their random motions in relation to new self-organization processes. He also gives a detailed description of applications of the general theory to various research fields, including the interaction of powerful radiation with matter, controlled thermonuclear research, etc.

During the 30 years of space exploration, important discoveries in the near-earth environment such as the Van Allen belts, the plasmapause, the magnetotail and the bow shock, to name a few, have been made. Coupling between the solar wind and the magnetosphere and energy transfer processes between them are being identified. Space physics is clearly approaching a new era, where the emphasis is being shifted from discoveries to understanding. One way of identifying the new direction may be found in the recent contribution of atmospheric science and oceanography to the development of fluid dynamics. Hydrodynamics is a branch of classical physics in which important discoveries have been made in the era of Rayleigh, Taylor, Kelvin and Helmholtz. However, recent progress in global measurements using man-made satellites and in large scale computer simulations carried out by scientists in the fields of atmospheric science and oceanography have created new activities in hydrodynamics and produced important new discoveries, such as chaos and strange attractors, localized nonlinear vortices and solitons. As space physics approaches the new era, there should be no reason why space scientists cannot contribute, in a similar manner, to fundamental discoveries in plasma physics in the course of understanding dynamical processes in space plasmas.

My goal in writing this book was to provide an introduction to meteorite science and a handbook on meteorite classification. Insofar as I succeeded it should prove useful both to the practicing professional and to university students at the upper-division and graduate levels. I originally intended the book to be nearly twice as long. The second half was to be a review of properties relating to the origin of each group of meteorites. Chapter XVIII is an example of how these later chapters would have looked, although most would not have been as interpretative. These chapters would have been useful chiefly to meteorite researchers looking for a quick summary of group properties; they were not written because of lack of time. Perhaps I will start to prepare this "second volume" in a year or so when my family and I have recovered from the preparation of the present volume. Although some parts of the classification portion are mildly icono clastic, I have attempted either to avoid the inclusion of speculative interpretations or to flag them with a caveat to the reader. I have relaxed these principles somewhat in Chapter XVIII to conserve space, but even there the discussion of alternative speculations should give the reader a feeling for the degree of uncertainty attached."

"Interplanetary Outpost" follows the mission architecture template of NASA's plan for Human Outer Planet Exploration (HOPE), which envisions sending a crew to the moon Callisto to conduct exploration and sample return activities. To realize such a mission, the spacecraft will be the most complex interplanetary vehicle ever built, representing the best technical efforts of several nations. A wealth of new technologies will need to be developed, including new propulsion systems, hibernation strategies, and revolutionary radiation shielding materials. Step by step, the book will describe how the mission architecture will evolve, how crews will be selected and trained, and what the mission will entail from launch to landing. However, the focus of "Interplanetary Outpost" is on the human element. The extended duration, logistical challenges, radiation concerns, communication lag times, isolation, and deleterious effects on the human body will conspire to not only significantly impair human performance but also affect the behavior of crewmembers. This book addresses each of these issues in detail while still providing the reader with a background to the necessary elements comprising such a mission.

The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a readable book about the entire essence of the satellite communication field.

This volume consists of invited talks and contributed papers presented at the NATO Advanced Study Institute "The Post Recombination Universe" which was held in Cambridge in the summer of 1987. There have, in recent years, been numerous meetings devoted to problems in observational cosmology. The attention given reflects the exciting rate of de velopment of the subject, and a survey of the proceedings from these symposia reveals that a great deal of emphasis has been given to consideration of the very early universe on the one hand, and to large scale structure in the universe at the present epoch on the other. The theme of this meeting was chosen to comple ment these efforts by focussing on the state of the universe at quite early times, but at those epochs which are still accessible to direct observations. The meet ing provided a broad coverage of the post recombination universe by drawing on experts from a wide variety of fields covering theory, background radiation fields and discrete sources at high redshift. Events in the moderately early universe will have left their mark in a great range of wavebands, from X-rays to the microwave region, and the evolution of the universe can be revealed by studies of the inter galactic medium, gravitational lensing and the abundance and clustering of high redshift sources. All of these subjects received much attention at the meeting, and the papers demonstrate the rich interplay between these areas in the rapidly expanding world of observational cosmology."

Space scientists and engineers belonging to the professional societies associated with the International Astronautical Federation gathered together in Vienna to hold the Federation's 23rd Congress. A selected number of papers and critical surveys that were presented and debated at this Congress and which span the widely diversified field of astonautics are collected in the present Proceedings, together with a number of summaries of Round Table Discussions andjor Forum Sessions. As its predecessors in the series, Astronautical Research 1972 constitutes an indispensable reference for several groups of people: those who are actively engaged in astronautics; those who are interested in following and assessing, year by year, the developments in astronautics, its progress, its new directions in research; and those who are concerned with its many applications. Space science and technology are bound to play an increasing role in the immediate future, now that greater effort is being devoted to the exploitation of their relevance to other fields of human activity. Problems posed by the scarcity of earth resources and by their inadequate management, pollution problems, problems created by man's indiscriminate and often irresponsible action in vital sectors of the biosphere can be tackled and successfully alleviated, if not solved, by means of the soft and hard advanced technology developed for space systems.

Communication satellites are a $144 billion industry. Is there any space-based industry that could possibly beat that market? 'Solar Power Satellites' shows why and how the space satellite industry will soon begin expanding its market from relaying signals to Earth to generating energy in space and delivering it to the ground as electricity. In all industrialized nations, energy demand is growing exponentially. In the developing world, the need for energy is as basic as food and water. The Sun's energy is available everywhere, and it is non-polluting. As business plans demonstrate its technical feasibility, commercial potential, and environmental acceptability, every country on Earth will look to space for the power it needs.

Grappling with Gravity explores the physiological changes that will occur in humans and the plants and animals that accompany humans as we move to new worlds, be it to colony in the emptiness of space or settlements on the Moon, Mars, or other moons or planets. This book focuses on the biomedical aspects, while not ignoring other life-changing influences of space living. For example, what happens to people physiologically in the microgravity of space, where weight and the direction "up" become meaningless? Adapting to microgravity represents the greatest environmental challenge that life will have encountered since our ancestors moved from the seas to solid Earth. Away from Earth the human body will begin almost immediately to adapt and change, to be able to function in these strange environments. As a person adapts in space he or she will become less fit to live on Earth.

We are extremely grateful to Springer-Verlag and to Prof. Dr. W. BeiglbOck for bring ing out the English edition of our book. We are also thankful to Dr. R. S. Wadhwa for a qualified translation. While preparing the manuscript for translation, we took the opportunity to go through the whole text, make necessary amendments, supplement the original material with new results, and considerably enlarge the lists of references. We hope that this book will serv to strengthen the bonds of international coopera tion in this field. July 1986 The authors Translator's Note The final form of the bibliography contains a (free) English translation of all the Russian books and papers published in the USSR. This has been done at the request of the authors and with the concurrence of Prof. BeiglMck. The titles are not always exact, and some of the works have already been translated into English or other European languages. Unfortunately, the authors were not in a position to provide detailed information on this subject. R.S. Wadhwa Preface to the Russian Edition What shall I do ... With their weightlessness In this ponderous world? M. Tsvetaeva, The Poet This book deals with the behavior of a liquid in zero-gravity or conditions close to it. The surge of interest in zero-gravity problems stems from the progress attained in the field of spaceflight, where such conditions can be attained for long periods of time."

Scientists in the late twentieth century are not the first to view galaxy formation as a phenomenon worthy of explanation in terms of the known laws of physics. Already in 1754 Kant regarded the problem as essentially solved. In his Univerlal Natural Hutory and Theory 0/ the H eaven$ he wrote; "If in the immesurable space in which all the suns of the Milky Way have formed themselves, we assume a point around which, through some cause or other, the first formation of nature out of chaoo began, there the largest mass and a body of extraordinary attraction will have arisen which has thereby become capable of compelling all the systems in the process of being formed within an enormous sphere around it, to fall towards itself as their centre, and to build up a system around it on the great scale . . . . Observation puts this conjecture almost beyond doubt. " More than 200 years later, a similar note of confidence was voiced by Zel'dovicb at an IAU symposium held in Tallin in 1911; "Extrapolating . . . to the next symposium somewhere in the early eighties one can be pretty sure that the question of the formation of galaxies and clusters will be solved in the next few years. " Perhaps few astronomers today would share Kant's near certainty or feel that Zel'dovich's prophecy has been fulfilled, Many, however, will sympathize with the optimistic olltlook of these two statements.

In summary, we can conclude that the contributions of the different ionization processes to the total ionization rate for the most abundant interstellar species are basically known. The ionization of the noble gases He and Ne is almost completely dominated by photoionization, whereas for H charge-exchange with the solar wind is most important. For other species, such as 0 and Ar, both processes contribute significantly. Electron impact ionization can typically contribute by '" 10% to the total rate in the inner Solar System. Because direct measurements of the solar EUV flux are not yet continuously available, the variation of the ionization rate over the solar cycle still contains a relatively large uncertainty. The recent measurements of pickup ion distributions and of the neutral helium gas provide an independent tool to determine the total ionization rate that can be used to cross calibrate with the results obtained for the individual ionization processes. Acknowledgements The authors are grateful to M. Allen for supplying us with new data on photoioniza tion cross-sections compiled by him. We thank also M. Gruntman for drawing our attention to and support in collecting the most recent data on charge-exchange cross-sections. D. R. was supported by grant No. 2 P03C. 004. 09 from the Com mittee for Scientific Research (Poland). This work was also supported in part through NASA contract NAS7-918, NSF Grant INT-911637, NASA Grant NAGW- 2579.

Featuring a foreword by the astronaut Ulf Merbold, this book is devoted to interfaces between two fluids, that is, between a liquid and a gas or between two liquids. It is the first review on the subject, providing an up-to-date overview.