Although transits of planets across the Sun are rare (only Mercury and Venus orbit the Sun closer than us, and so can transit the Sun's disc) amateur astronomers can observe, record and image other kinds of transit, which are very much more frequent. Transit is in two parts, the first telling the fascinating story of the early scientific expeditions to observe transits. The second part is for practical observers, and explains how to observe transits of all sorts - even transits of aircraft as they fly between the observer and the Sun!

The question of the existence of other worlds and other living beings has been present in the human quest for knowledge since as far as Epicurus. For centuries this question belonged to the fields of philosophy and theology. The theoretical problem of the formation of the Solar System, and hence of other planetary systems, was tackled only during the 18th century, while the first observational attempts for a detection started less than one hundred years ago. Direct observation of an extra-solar planetary system is an extraordinarily difficult problem: extra-solar planets are at huge distances, are incredibly faint and are overwhelmed by the bright light of their own stars. With virtually no observational insight to test their models, theoreticians have remained for decades in a difficult position to make substantial progress. Yet, the field of stellar formation has provided since the 1980s both the the oretical and observational evidences for the formation of discs at the stage of star birth and for debris materials orbiting the very young stellar systems. It was tempting to consider that these left-overs might indeed later agglomerate into planetary systems more or less similar to ours. Then came observational evidences for planets outside the Solar System.

Transient phenomena are short-lived astronomical events, unusual in a science in which time is more often measured in millennia than milliseconds. There is a fascination with transient phenomena, predictable or otherwise, that astronomers of all abilities share. In Meteors, Comets, Supernovae, Neil Bone gives guidelines for observers, including the best possible periods (months or years) to see seasonal but unpredictable phenomena like meteors and sunspots. Recording such outbursts involves visual observing techniques, photography, and even the relatively new field of the video recording of meteors, which are also examined in detail. The book also includes material about phenomena that occur in the lower atmosphere (such as "ozone eaters", nacreous clouds, solar and lunar haloes), which although not strictly astronomical in their nature attract the attention of dedicated sky-watchers.

The Quest To Discover Life Beyond Earth.

"The 'dreams' that I write of are not the usual ones, the images that come up in our minds involuntarily during certain stages of sleep, but rather the hopes and expectations that we have lavished upon other worlds around us."—from the Preface.

The surprisingly long history of debate over extraterrestrial life is full of marvelous visions of what life "out there" might be like, as well as remarkable stories of alleged sightings and heated disputes about the probability that life might actually have arisen more than once. In Planetary Dreams, acclaimed author Robert Shapiro explores this rich history of dreams and debates in search of the best current answers to the most elusive and compelling of all questions: Are we alone?

In his pursuit, he presents three contrasting views regarding how life might have started: through Divine Creation, by a highly unlikely stroke of luck, or by the inevitable process of a natural law that he terms the Life Principle. We are treated to a lively fictional dinner debate among the leading proponents of these schools of thought—with the last named group arguing that life has almost surely formed in many places throughout the universe, and the others that life may well be entirely unique to our own blue planet. To set the stage for a deep exploration of the question, the author then leads us on a fantastic journey through the museum of the cosmos, an imagined building that holds models of the universe at different degrees of magnification. We then journey deep into inner space to view the astonishingly intricate life of a single cell, and learn why the origin of such a complex object from simple chemical mixtures poses one of the most profound enigmas known to science.

Writing in a wonderfully entertaining style, Shapiro then reviews the competing theories about the start of life on Earth, and suggests the debate may best be settled by finding signs of life on the other worlds of our solar system. He takes us on a guided tour of the most likely sites, from the underground hot springs of Mars to the ice-covered oceans of Jupiter's airless moons.

Along the way, he shares a wealth of fascinating stories about the ways in which our views of the heavens have changed, from the theories of ancient philosphers, who argued that the Moon was inhabited, to the current Origins and Astrobiology initiatives of NASA. He describes the probes that will be sent out in the near future in pursuit of the first compelling physical evidence of life beyond Earth, and concludes with a radical suggestion about how this quest might be supported through the next millennium. As we launch into an exciting new era of space exploration, Planetary Dreams offers a thoughtful and entertaining exploration of both the history of our hopes and expectations and a vision of a possible future in which the discovery of life elsewhere will provide a new view of our place in the universe.

The cover picture of this volume displays one of the most advanced products of he lioseismic research: a view into the deep interior of the sun, revealing its distinctly non-uniform rotation throughout the entire depth of the convection zone. Just over 20 years ago, the first successful helioseismic experiment disclosed an increase of ro tation velocity in the uppermost one dozen megameters below the photosphere. The stunning progress in depth and detail highlighted by the cover diagram (and by others shown in this volume as well) was made possible by considerable advances in instru mentation, by the development of powerful analytical tools and, foremost, by the involvement of new brains of enthusiastic proselytes and newcomers to the field, in creasing nearly exponentially in number every year. New branches of research widened the scope of "uranoseismology", as e. g. time-distance seismology (the promising av enue towards small-scale and short-time variability), atmospheric seismology (a new look at strange phenomena we have all ways seen, but hardly understood), and finally the growing observational assault on hundreds of individual stars which are either manifestly or supposedly oscillating -i. e. asteroseismology. The formation of numer ous solar and stellar observing networks and, ultimately, space missions like SOHO have greatly promoted the potential of this science. This steady progress was accompanied by workshops, colloquia, and symposia in quick succession.

Ce volume contient les revues invitees et les presentations orales du Symposium VAl 181 Sounding Solar and Stellar Interiors, tenu a Nice du 30 septembre au 3 octobre 1996. Les posters presentes a cette conference 1 sont publies dans un volume separe. Depuis Ie lancement avec succes du satellite SoRO Ie 2 Decembre 1995, et apres des annees d'efforts importants dans Ie domaine de l'helio- et l'asterosismologie, il a semble approprie de tenir un symposium dedie aux consequences de la sismologie pour notre connaissance de la structure in- terne du Soleil et des etoiles. Le but etait de presenter a la communaute entiere les nouveaux resultats de l'heliosismologie obtenus aussi bien par les experiences spatiales que par les reseaux exist ants au sol, ainsi que les avancees theoriques dans les domaines de la structure et de la physique de l'interieur solaire. Ce but a ete largement atteint: alors que SoRO ne fournissait des don- nees que depuis environ 6 mois, la qualite des donnees heliosismologiques a ete largement amelioree, de nouvelles techniques ont ete elaborees comme la "telechronosismologie" (nom propose par D. Gough dans sa conclusion pour l'analyse temps-distance), et de nouveaux mecanismes physiques ont ete proposes pour tenter de reduire les differences persist antes entre Ie Soleil observe et les modeles standard.

A total eclipse of the Sun is due in August 1999. It will attract alot of interest because - unusually - it will be visible in much of Europe and the UK. A total Solar Eclipse is always fascinating. This book is for everyone that wants to know 1. What a Solar Eclipse is 2. The phenomena one can expect to see 3. How to photograph an eclipse using a variety of methods 4. How to plan for an eclipse expedition. The book not only covers the 1999 eclipse but also past and future eclipses which we can look forward to. This book is also interesting to "armchair astronomers" as it contains alot of historical and anecdotal information. There's even a final chapter on "Eclipse Mishaps and Oddities" including the American eclipse expedition of 1780 that missed the total eclipse because they went to the wrong location

In the past decade, indirect (Doppler) imaging techniques have opened up a whole new discipline in stellar astronomy, providing increasingly detailed photometric, magnetic, and chemical inhomogeneity images of stellar surfaces. Furthermore, new optical interferometers are already being used with sophisticated interferometer techniques to image stellar surface structures more directly, and in the future the ESO VLT Interferometer and other instruments will extend these capabilities enormously. These developments are highlighted in the first two sections of this book. The large number of recent results, ground-based and space-based, and the lack of a generally accepted dynamo theory with predictive power for the stars and the Sun, result in an ever-growing complexity of interpretation of individual results. The IAU Symposium 176 on Stellar Surface Structure' consequently focused on spatially resolved stellar observations throughout the H-R diagram, from O- and B-stars to late M-stars. Two further sections in this book summarize the current observational data on surface inhomogeneities in stellar photospheres, chromospheres, and coronae. Finally, a special section is devoted to next generation model atmospheres.

On July 16, 1994 a world-shattering event occurred that would rivet our attention for six explosive days and go on to make history as the single most important celestial event of the century. Comet Shoemaker-Levy 9 crashed into Jupiter, changing forever our understanding of comets and cosmic cataclysms. Our own sense of security would never be the same as the world witnessed fragment after fragment of the comet bash into Jupiter with the collective equivalent force of a 50-million-megaton bomb. David Levy, co-discoverer of periodic Comet Shoemaker-Levy 9, shares his once-in-several-lifetimes' story from the time of the discovery, with Eugene and Carolyn Shoemaker, of this unusual "squashed" comet to the later shocking revelation of hearing that "their" comet was destined to collide with Jupiter. Never in recorded history has a comet created such a catastrophic event as smashing into a planet. Impact Jupiter takes off where David Levy's earlier acclaimed book, The Quest for Comets, left us. Magnificent photos of the impacts, including superb color pictures, accompany David's poetic words, vividly bringing to life his thrilling story. Savor the words of one of the world's most celebrated amateur astronomers as he humbly and eloquently opens the beauty of the heavens to all who are curious.

This book provides a concise but broad overview of the engineering, science and flight history of planetary landers and atmospheric entry probes designed to explore the atmospheres and surfaces of other planets. It covers engineering aspects specific to such vehicles which are not usually treated in traditional spacecraft engineering texts. Examples are drawn from over thirty different lander and entry probe designs that have been used for lunar and planetary missions since the early 1960s. The authors provide detailed illustrations of many vehicle designs from different international space programs, and give basic information on their missions and payloads, irrespective of the mission's success or failure. Several missions are discussed in more detail to demonstrate the broad range of the challenges involved and the solutions implemented. This will form an important reference for professionals, academic researchers and graduate students involved in planetary science, aerospace engineering and space mission development.

A complete revision of Goody's classic 1964 work, this volume offers a systematic discussion of atmospheric radiation processes that today are at the center of worldwide study and concern. It deals with the ways in which incident solar radiation is transformed into scattered and thermal radiation, and the thermodynamic consequences for the Earth's gaseous envelope, identifying aspects of the interaction between radiation and atmospheric motions as the central theme for atmospheric radiation studies. As a complete treatment of physical and mathematical foundations, the text assumes no prior knowledge of atmospheric physics. The theoretical discussion is systematic, and can therefore be applied with minor extension to any planetary atmosphere.

Meteorites - as well as shooting stars and meteors - result from a collision of a solid body from space with our Earth, but only meteorites are able to penetrate the Earth's protective shield, the atmosphere, and fall to the Earth's surface. Apart from lunar samples, they are the only materials from beyond the Earth which we can probe and study.
This book gives a concise and up-to-date description of meteorites - fall phenomena, chemical and mineral composition, classification - as well as a discussion of their formation and origin, which also tells us the story of the formation of our planetary system. The text is understandable for laymen and students, but can also be used as an introduction to the field for students and scientists.

It is a pleasure to present this work, which has been well received in Gennan-speaking countries through four editions, to the English-speaking reader. We feel that this is a unique publication in that it contains valuable material that cannot easily-if at all-be found elsewhere. We are grateful to the authors for reading through the English version of the text, and for responding promptly (for the most part) to our queries. Several authors have supplied us, on their own initiative or at our suggestion, with revised and updated manuscripts and with supplementary English references. We have striven to achieve a translation of H andbuch flir Sternfreunde which accurately presents the qualitative and quantitative scientific principles con tained within each chapter while maintaining the flavor of the original Ger man text. Where appropriate, we have inserted footnotes to clarify material which may have a different meaning and/or application in English-speaking countries from that in Gennany. When the first English edition of this work, Astronomy: A Handbook (translated by the late A. Beer), appeared in 1975, it contained 21 chapters. This new edition is over twice the length and contains 28 authored chap ters in three volumes. At Springer's request, we have devised a new title, Compendium of Practical Astronomy, to more accurately reflect the broad spectrum of topics and the vast body of infonnation contained within these pages.

THE MEETING The IAU Symposium 160 ASTEROIDS COMETS METEORS 1999 has been held at Villa Carlotta in Belgirate, on the shore of Lago Maggiore (Italy), from June 14 to June 18, 1993. It has been organized by the Astronomical Observatory of Torino and by the Lunar and Planetary Institute of Houston. It has been a very large meeting, with 323 registered participants from 38 countries. The scientific program included 29 invited reviews, 106 oral communications, and 215 posters. The subjects covered included all the aspects of the studies of the minor bodies of the solar system, including asteroids, comets, meteors, meteorites, interplanetary dust, with special focus on the interrelationships between these. The meeting was structured as follows. 5 morning plenary sessions have been devoted to invited reviews on: (1) search programs (2) populations of small bodies (3) dynamics (4) physical observations and modelling (5) origin and evolution. Two afternoon plenary sessions have been devoted to space missions to small bodies and to interrelationships between the different populations. The afternoon parallel sessions have been devoted to: dynamics of comets; Toutatis, Ida, Gaspra; physical processes in cometary comae and tails; meteorites; the cosmogonic message from cometary nuclei; physics of asteroids; the interplanetary dust complex; comet nuclei; meteors; composition and material properties of comets; dynamics of asteroids.

The brilliant trailing beauty of fiery comets has inspired fear, wonder, and awe since the dawn of human history. Brighter than stars, moving and disappearing in their own singular orbits, comets have been among the most mysterious elements in the sky, eluding our understanding until very recently. With the aid of space probes, scientists have discovered that these swiftly moving chunks of ice and carbon are more plentiful and far more dangerous than suspected. Scientists are also beginning to realize the monumental role played by comets in the development of the Earth and solar system. David Levy describes in dramatic detail the thrilling yet often devastating effects of comet collisions. In the dawn of our solar system, the Earth was barraged with comets that may have carried the materials necessary to lay the foundations for life on this planet. Levy also presents compelling evidence for later comet collisions, including those of the age of dinosaurs. Great impacts, Levy asserts, not only caused the extinction of the dinesaurs, but ushered in new species of life. As Levy so clearly explains, scientists are realizing that comet collisions are virtually inevitable. Levy reveals possible future collisions with the Earth and describes the terrible risks to life they would pose. He even shows how we might prepare to withstand the impact of large comets in the future.

This introduction to planetary geology concentrates on the surface features of the planets and satellites of our Solar System. The author first discusses the primary processes that shape our planet, Earth, and the geomorphology of the objects in the Solar System. The second edition includes new information about Venus and a new chapter on Neptune. The book is beautifully illustrated with high-resolution black-and-white photographs from recent space probes and orbiting spacecraft, and with explanatory diagrams. Each chapter starts with a description of the general physiography and terrain units, then the geomorphic processes that created them are discussed. Finally a synopsis of the geologic evolution of the surface is given. The selected references at the end include original papers, review articles and books.

Infrared Solar Physics contains the proceedings of the 154th Symposium of the International Astronomical Union held in Tucson, Arizona, March 2--5, 1992. Aimed at active workers and graduate students in solar physics, this volume provides the first comprehensive view of a rapidly expanding discipline that gives us a new perspective on the sun. Measurements across the wide infrared spectral range -- here, from 1 mum to 1 mm -- can probe the solar atmosphere from below the visible surface through the outer reaches of the corona. Taking full advantage of revolutionary advances in detector technology, infrared observations from the ground, aircraft and space have led to a better understanding of solar magnetic fields, atmospheric structure and activity, and elemental abundances. The infrared has also provided new interpretive challenges, such as the appearance of the 12-mum emission lines of magnesium. These and other developments are discussed here by the leading contributors to the field, who also give their perspectives on the future of this rich field of study.

This IAU-symposium was the first which was entirely dedicated to dynamo processes, which are fundamental on all cosmical scales. Dynamo theory concerns one of the few truly key questions of recent cosmic physics. There is increasing evidence for the magnetic character of most short-term activity phenomena in astrophysics. Obviously, the tria. ngle "gravil;y, nuclea. r power, magnetism" dictates cosmic evolution over a very broad scale of magnitudes. A complicated interplay of rotation, magnetism and turbulence, that is hard to resolve, determines stellar and galactic activity for almost all the short and medium time- scales. Behind these multiform phenomena, the cosmic dynamo works in various guise. . "I, all involving inductive and dissipative equilibria in rotating turbulent cosmic plasmas. The Sun, representing the cosmic dynamo par excellence, stands from the be- ginning at the centre of interest for those who followed the dynamo idea. Even the first models were able to present an explanation of the typical structural appear- ance of the solar magnetic field, i. e. a 22 year cycle, activit. y belts and their zonal migration, antisymmetry of t. he magnetic polarity. However, the solar dynamo still provides topics of further discussions, since confrontation with recent observational data raised and stoill raises new questions, nOll of whicll have yet found a plausible answer. These questions represent a challenge for the development of the basic the- ories: Understanding of turbulence, especially Ilsing methods of modern nonlinear physics. Numerical simulations arc promising in the ncar future.

Discover the wonders of the Universe with this complete introduction to observing and understanding the night sky. This practical guide explains and demystifies stargazing, teaching you to recognize different kinds of objects and showing you how they move through the sky over the course of the night and the year. It shows you how to understand and enjoy the cosmos, building your practical astronomy skills from the basics to more advanced techniques. Beginning with an explanation of the Universe itself - how big is it, what shape is it, how old is it, and will it end? - it then takes you on a tour around the night sky, building up your knowledge in simple stages. Practical advice begins with naked-eye observations, then illustrated step-by-step instructions show you how to set up and use binoculars and telescopes, and how to take your own pictures of the night sky. It also lets you take a closer look at the different objects you can view in the night sky, telling you how to train your eye to recognize basic patterns of stars (constellations) and how to tell planets apart from other celestial bodies, showing you how to observe them in an innovative step-by-step way. An atlas of the night sky is also included, with charts that can be used in both the northern and southern hemispheres throughout the year. Accessible, inspirational, and authoritative, Stargazing for Beginners will enthuse and inform anyone who wants to expand their knowledge of the night sky.

This symposium was devoted to a new celestial mechanics whose aim has become the study of such `objects' as the planetary system, planetary rings, the asteroidal belt, meteor swarms, satellite systems, comet families, the zodiacal cloud, the preplanetary nebula, etc. When the three-body problem is considered instead of individual orbits we are, now, looking for the topology of extended regions of its phase space. This Symposium was one step in the effort to close the ties between two scientific families: the observationally-oriented scientists and the theoretically-oriented scientists.

As in all other fields of astronomy, progress in instrumentation and observational techniques has in recent years brought a wealth of new information about the sun. This introduction presents a complete overview of solar physics, of what we know and would like to know. The increasing number of observations of solar pheno- mena on neighbouring stars makes this book valuable not only for students specializing in solar physics but also for researchers interested in stellar structure and the solar-stellar connection.

Much of the excitement in modern Solar Physics has come from the realisation that the Sun is a plasma and that this plasma is interacting with the magnetic field in a wide variety of subtle ways. As well as being of great interest in their own right the observed plasma phenomena on the Sun are of much wider importance, since they reveal to us details of basic phenomena that are expected to be occurring throughout the universe. It was with this in mind that 173 solar physicists from 17 countries gathered together in Bangalore with an air of anticipation. We were not disappointed as we received the warmest of welcomes from our graceful and charming host, Vinod Krishan. She and her colleagues worked tirelessly to make our stay a most memorable one and to ensure that the meeting ran with calm and efficiency. In addition to being stimulated by an excellent series of talks on the up-to-the minute advances in our subject, it was a pleasure to make new friendships from so many countries and to learn, in particular, of the Solar Physics being done in India which has a great tradition and is of a high standard. Furthermore, we enjoyed hearing about Indian culture and appreciating its beauty, especially on our day's tour into the countryside to visit some Hindu and Jain temples."

Stellar flares represent one of the most challenging problems of contemporary astrophysics. Both solar and stellar observations have shown the flare phenomenon to be very complex, and in recent years important progress has been made from simultaneous observations over wide wavelength ranges. Some similarities exist between solar and stellar flares, but im portant differences have also been established. Such topics, as well as theoretical aspects, were discussed in detail at the Palo Alto IAU Colloquium No. 104, Solar and Stellar Flares, in 1988. Another approach to the study of stellar flares is through observations of flare stars in physical systems. The possibility of detecting flare stars in star clusters and associations with wide angle telescopes have allowed observations of systems with quite different ages. The classical works of G. Haro and V. A. Ambartsumian demonstrated the evolutionary nature of the flare phenomenon. Flares occur at the earliest stages of dwarf star evolution. The photographic observations of flare stars in systems of different ages turned out to be significant not only for the evolutionary study of flare stars, but also for the study of their physical nature. This observational fact was conditioned by very large diversity of flare star luminosities, i.e. of scales of flares produced by them and by peculiarities of stellar flares observed in star clusters and associations."

This Symposium, the first devoted entirely to the measurement and the role of magnetic fields in the non-solar Universe, was held in Heidelberg, on June 19-23, 1989. The meeting began with review talks on magnetic phenomena near the solar photosphere, corona, and in stellar winds, since these nearby "laboratories," studied for many years, provide much of the prior knowl edge of magnetic effects in astrophysical plasmas. The Symposium contained presentations of considerable new work concerning the role of magnetic fields in accretion disks, bipolar outflows, and related magnetic phenomena in molecular clouds and star forming regions. Both observa tions and related theory of the large-scale magnetic fields in the Milky Way were covered, in addition to a session on the more general theme of magnetohydrodynamics of galactic magnetic fields. Dynamo mechanisms were discussed in considerable detail. It was apparent that recent observational data on polarized emission from external galaxies are now of sufficiently high quality that meaningful tests of large-scale field amplification, and of ideas on the origin of galactic magnetic fields, can be undertaken. Both new observations and numerical simulation work were described in the context of active galaxy nuclei, supernova remnants, radio source jets and extended lobes, and also in the environment of galaxy clusters. Recent large-scale computer simulations incorporating magnetic fields in star formation, radio source jets, and many other phenomena were presented, and much of this was very new."