Short Historical Overview In the 1940s, two phenomena in the ?eld of cosmic rays (CR) forced scientists to think that the Sun is a powerful source of high-energy particles. One of these was discovered because of the daily solar variation of CR, which the maximum number of CR observed near noon (referring to the existence of continuous ?ux of CR from the direction of the Sun); this became the experimental basis of the theory that CR's originate from the Sun (or, for that matter, from within the solar system) (Alfven 1954). The second phenomenon was discovered when large ?uxes of high energy particles were detected from several solar ?ares, or solar CR. These are the - called ground level events (GLE), and were ?rst observed by ionization chambers shielded by 10 cm Pb (and detected mainly from the secondary muon-component CR that they caused) during the events of the 28th of February 1942, the 7th of March 1942, the 25th of July 1946, and the 19th of November 1949. The biggest such event was detected on the 23rd of February 1956 (see the detailed description in Chapters X and XI of Dorman, M1957). The ?rst phenomenon was investigated in detail in Dorman (M1957), by ?rst correcting experimental data on muon temperature effects and then by using coupling functions to determine the change in particle energy caused by the solar-diurnal CR variation."

This book records our current understanding of the observational and theoretical properties of objects known as ultracool dwarfs. It covers the state of the art in this new field. It is split into theoretical, observational and spectral classification sections. Each subject area begins with an introduction by an eminent scientist. It covers a wide range of issues, such as the transition from L to T dwarfs, dust and alkali metal modelling, companions, activity, the deuterium test, and brown dwarf variability, and contains considerable discussion about spectral classification schemes. The articles arose from an IAU meeting and they address researchers as well as graduate students.

This classic text, aimed at senior undergraduates and beginning graduate students in physics and astronomy, presents a wide range of astrophysical concepts in sufficient depth to give the reader a quantitative understanding of the subject. Emphasizing physical concepts, the book outlines cosmic events, but does not portray them in detail - it provides a series of astrophysical sketches. For this third edition, nearly every part of the text has been reconsidered and rewritten; new sections have been added to cover recent developments, and most of the rest has been revised and brought up to date. The book begins with an outline of the scope of modern astrophysics and the elementary problems concerning the scale of cosmic objects and events. The basic physics needed to answer these questions is developed in the next chapters, using specific astronomical processes as examples. The second half of the book enlarges on the topics introduced at the beginning and shows how we can obtain quantitative insights into the structure and evolution of stars, the dynamics of cosmic gases, the large-scale behavior of the universe, and the origins of life. supernovae, comets, quasars) are mentioned throughout the text whenever the relevant physics is discussed rather than in individual sections. To compensate, there is an appendix that gives a brief background of astronomical concepts for students unfamiliar with astronomical terminology, as well as a comprehensive index. The extensive bibliography refers to other sources that treat individual topics in detail.

Starting in 1995 numerical modeling of the Earth's dynamo has ourished with remarkable success. Direct numerical simulation of convection-driven MHD- ow in a rotating spherical shell show magnetic elds that resemble the geomagnetic eld in many respects: they are dominated by the axial dipole of approximately the right strength, they show spatial power spectra similar to that of Earth, and the magnetic eld morphology and the temporal var- tion of the eld resembles that of the geomagnetic eld (Christensen and Wicht 2007). Some models show stochastic dipole reversals whose details agree with what has been inferred from paleomagnetic data (Glatzmaier and Roberts 1995; Kutzner and Christensen 2002; Wicht 2005). While these models represent direct numerical simulations of the fundamental MHD equations without parameterized induction effects, they do not match actual pla- tary conditions in a number of respects. Speci cally, they rotate too slowly, are much less turbulent, and use a viscosity and thermal diffusivity that is far too large in comparison to magnetic diffusivity. Because of these discrepancies, the success of geodynamo models may seem surprising. In order to better understand the extent to which the models are applicable to planetary dynamos, scaling laws that relate basic properties of the dynamo to the fundamental control parameters play an important role. In recent years rst attempts have been made to derive such scaling laws from a set of numerical simulations that span the accessible parameter space (Christensen and Tilgner 2004; Christensen and Aubert 2006).

Proceedings of the Workshop held at the University of Rome, March 24-28, 1980

This publication is a result of three meetings, each 5 days long, held at the Goddard Space Flight Center on January 24-28, 1983, June 8-14, 1983, and February 13-17, 1984. The meetings were held in the interim between the full operations of the Solar Maximum Mission (SMM) in 1980, and the renewed operations after its repair in orbit in April 1984. Their general objectives were as follows: o Synthesize flare studies after three years of SMM data analysis. Many analyses of individual flares and individual phenomena, often jointly across many data sources had been published, but a need existed for a broader synthesis and updating of our understanding of solar flares since the Skylab Flare Workshops held several years earlier. o Encourage a broader participation in the SMM data anlysis and combine this more fully with theory and other data sources--data obtained with other spacecraft such as the HINOTORI, P78-1, and ISEE-3 spacecrafts, and with the Very Large Array (VLA) and many other ground-based instruments. Many coordinated data sets, unprecedented in their breadth of coverage and multiplicity of sources, had been obtained within the structure of the Solar Maximum Year (SMY). o Stimulate joint studies, and publication in the general scientific literature. The intended primary benefit was for informal collaborations to be started or broadened at the Workshops with subsequent publications. o Provide a special publication resulting from this Workshop. o Provide a starting point of understanding for planning renewed full observations with the repaired SMM.

Introduction to Cosmology provides a rare combination of a solid foundation of the core physical concepts of cosmology and the most recent astronomical observations. The text is designed for advanced undergraduates or beginning graduate students and assumes no prior knowledge of general relativity. An emphasis is placed on developing the students' physical insight rather than losing them with complex math. An approachable writing style and wealth of fresh and imaginative analogies from "everyday" physics are used to make the concepts of cosmology more accessible.

This book provides overviews of the new reduction as well as on the use of the Hipparcos data in a variety of astrophysical implementations. A range of new results are included. The Hipparcos data provide a unique opportunity for the study of satellite dynamics as the orbit covered a wide range of altitudes, showing in detail the different torques acting on the satellite. The book is accompanied by a DVD with the new catalogue and the underlying data.

This book, in three parts, describes three phases in the development of the modern theory and calculation of the Moon's motion. Part I explains the crisis in lunar theory in the 1870s that led G.W. Hill to lay a new foundation for an analytic solution, a preliminary orbit he called the "variational curve." Part II is devoted to E.W. Brown's completion of the new theory as a series of successive perturbations of Hill's variational curve. Part III describes the revolutionary developments in time-measurement and the determination of Earth-Moon and Earth-planet distances that led to the replacement of the Hill Brown theory in 1984.

This book is based partly on a. lecture course given at the University of Tri este, but mostly on my own research experience in the field of galactic chemical evolution. The subject of galactic chemical evolution was started and developed by Beat rice Tinsley in the seventies and now is a flourishing subject. This book is dedi cated to the chemical evolution of our Galaxy and aims at giving an up-to-date review of what we have learned since Tinsley's pioneering efforts. At the time of writing, in fact, books of this kind were not available with the exception of the excellent book by Bernard Pagel on "Nucleosynthesis and Chemical Evolution of Galaxies" (Cambridge University Press, 1997), and the subject of galactic chem ical evolution has appeared only as short chapters in books devoted to other subjects. Therefore, I felt that a book of this kind could be useful. The book summarizes the observational facts which allow us to reconstruct the chemical history of our Galaxy, in particular the abundances in stars and in terstellar medium; in the last decade, a great deal of observational work, mostly abundance determinations in stars in the solar vicinity, has shed light on the pro duction and distribution of chemical elements. Even more recently more abun dance data have accumulated for external galaxies at both low and high redshift, thus providing precious information on the chemical evolution of different types of galaxies and on the early stages of galaxy evolution."

This thesis by Cole Johnston brings novel insights into the inner workings of young massive stars. By bridging the observational fields of binary stars and asteroseismology this thesis uses state of the art statistical techniques to scrutinise theories of modern stellar astrophysics. Developing upon the commonly used isochrone fitting methodology, the author introduces the idea of isochrone cloud fitting in order to account for the full breadth of physics observed in stars. The author combines this methodology with gravity mode asteroseismic analysis to asses the level of chemical mixing deep within the stellar core in order to determine the star's age and core mass. Wrapped into a robust statistical framework to account for correlations, this methodology is employed to analyse individual stars, multiple systems, and clusters alike to demonstrate that chemical mixing has dramatic impact on stellar structure and evolution.

The reviews presented in this volume cover a huge range of cluster of galaxies topics. Readers will find the book essential reading on subjects such as the physics of the ICM gas, the internal cluster dynamics, and the detection of clusters using different observational techniques. The expert chapter authors also cover the huge advances being made in analytical or numerical modeling of clusters, weak and strong lensing effects, and the large scale structure as traced by clusters.

In physics, the idea of extra spatial dimensions originates from Nordstom s 5-dimensional vector theory in 1914, followed by Kaluza-Klein theory in 1921, in an effort to unify general relativity and electromagnetism in a 5 dimensional space-time (4 dimensions for space and 1 for time). Kaluza Klein theory didn t generate enough interest with physicist for the next five decades, due to its problems with inconsistencies. With the advent of supergravity theory (the theory that unifies general relativity and supersymmetry theories) in late 1970 s and eventually, string theories (1980s) and M-theory (1990s), the dimensions of space-time increased to 11 (10-space and 1-time dimension).

There are two main features in this book that differentiates it from other books written about extra dimensions: The first feature is the coverage of extra dimensions in time (Two Time physics), which has not been covered in earlier books about extra dimensions. All other books mainly cover extra spatial dimensions. The second feature deals with level of presentation. The material is presented in a non-technical language followed by additional sections (in the form of appendices or footnotes) that explain the basic equations and formulas in the theories. This feature is very attractive to readers who want to find out more about the theories involved beyond the basic description for a layperson. The text is designed for scientifically literate non-specialists who want to know the latest discoveries in theoretical physics in a non-technical language. Readers with basic undergraduate background in modern physics and quantum mechanics can easily understand the technical sections.

Part I starts with an overview of the Standard Model of particles and forces, notions of Einstein s special and general relativity, and the overall view of the universe from the Big Bang to the present epoch, and covers Two-Time physics. 2T-physics has worked correctly at all scales of physics, both macroscopic and microscopic, for which there is experimental data so far. In addition to revealing hidden information even in familiar "everyday" physics, it also makes testable predictions in lesser known physics regimes that could be analyzed at the energy scales of the Large Hadron Collider at CERN or in cosmological observations."

Part II of the book is focused on extra dimensions of space. It covers the following topics: The Popular View of Extra Dimensions, Einstein and the Fourth Dimension, Traditional Extra Dimensions, Einstein's Gravity, The Theory Formerly Known as String, Warped Extra Dimensions, and How Do We Look For Extra Dimensions?"

Comet nuclei are the most primitive bodies in the solar system. They have been created far away from the early Sun and their material properties have been altered the least since their formation. Thus, the composition and structure of comet nuclei provide the best information about the chemical and thermodynamic conditions in the nebula from which our solar system formed. In this volume, cometary experts review a broad spectrum of ideas and conclusions based on in situ measurement of Comet Halley and remote sensing observations of the recent bright Comets Hale-Bopp and Hyakutake. The chemical character of comet nuclei suggests many close similarities with the composition of interstellar clouds. It also suggests material mixing from the inner solar nebula and challenges the importance of the accretion shock in the outer nebula. The book is intended to serve as a guide for researchers and graduate students working in the field of planetology and solar system exploration. Several special indexes focus the reader's attention to detailed results and discussions. It concludes with recommendations for laboratory investigations and for advanced modeling of comets, the solar nebula, and the collapse of interstellar clouds.

The Solar-B satellite was launched in the morning of 23 September 2006 (06:36 Japan time) by the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), and was renamed to Hinode ('sunrise' in Japanese). Hinode carries three - struments; the X-ray telescope (XRT), the EUV imaging spectrometer (EIS), and the solar optical telescope (SOT). These instruments were developed by ISAS/JAXA in cooperation with the National Astronomical Observatory of Japan as domestic partner, and NASA and the Science and Technology Facilities Council (UK) as international partners. ESA and N- wegian Space Center have been providing a downlink station. All the data taken with Hinode are open to everyone since May 2007. This volume combines the ?rst set of instrumental papers of the Hinode mission (the mission overview, EIS, XRT, and the database system) published in volume 243, Number 1 (June 2007), and the second set of papers (four papers on SOT and one paper on XRT) published in Volume 249, Number 2 (June 2008). Another SOT paper cited as Tarbell et al. (2008) in these papers will appear later in Solar Physics.

Double and multiple stars are the rule in the stellar population, and single stars the minority, as the abundance of binary systems in the space surrounding the sun shows beyond doubt. Numerous stellar features, and methods of their exploration, ensue specifically from the one but widespread property, the binary nature. Stellar masses are basic quantities for the theory of stellar structure and evolution, and they are ob tained from binary-star orbits where they depend on the cube of observed parameters; this fact illustrates the significance of orbits as well as the accuracy requirements. Useful in dating stellar history is the knowledge that components of a system, different though they may appear, are of the same origin and age. Between star formation and the genesis of binaries a direct connection can be traced. The later stages of stellar life branch into a great variety as mutual influence between the components of a close binary pair develops. Transfer and exchange of mass and the presence of angular momentum in the orbit give rise to special tracks of evolution, not found for single stars, and to peculiar spectral groups. This is not a new story but it has a new ending: The patterns of evolution involving mass transfer appear to lead ultimately to single objects."

Our conference - opening today - has two aims in view: first, to commemorate some milestones in the development of the studies of close binary systems whose anniversaries fall in these years, as well as to take stock of our present knowledge accumulated through out preceding decades, in order to consider where do we go from here. This summer, 310 years will have elapsed since the first ec lipsing binary - Algol - was discovered in Bologna by Geminiano Montanari (1633-1687) to be a variable star; and 198 years have gone by since John Goodricke of York (1764-1786) established the fact that Algol's light changes were periodic. Moreover, it is al most exactly (to a month) now 100 years since Edward Charles Pickering (1846-1919) of Harvard Observatory in the United States took the first steps towards the development of systematic methods of analysis of the light changes of Algol and related systems - a topic which will constitute the major part of the programme of our present conference. The three dates recalled above illustrate that the discoverers of such celestial objects and observers of their light changes have been systematically ahead of the theoreticians endea vouring to understand the significance of the observed data by de cades and centuries in the past - a fact which, incidentally, con tinues to hold good (albeit with a diminishing lead-time) up to the present."

IAU Symposium No. 121 was hosted by the Byurakan Astrophysical Observatory in Soviet Armenia, almost 30 years after Ambartsumian's pioneering ideas about galaxy activity were first published and almost exactly 20 years after the first Byurakan IAU symposium on nuclear activity (No. 29, "Non-stable Phenomena in Galaxies, May 1966). Although the proceedings of the first Byurakan symposium were not published in English, that conference provided a definitive impulse to the field, as Ambartsumian's ideas had done 10 years earlier. The Byurakan Astrophysical Observatory was thus a particularly appropriate setting for IAU 121. The symposium was also very timely since many new exciting results were presented which will surely revolutionize many of our present ideas about nuclear activity in galaxies and QSO's. The first results of the by now famous Markarian survey were presented by B.E. Markarian in the first Byurakan conference. Unfortunately, his untimely death prevented him from attending the second conference, but the influence of his fundamental work was certainly felt.

The 10th ESLAB Symposium was held at Grossenzersdorf near Vienna on 10-13 June 1975 under the title 'The Scientific Satellite Programme During the Inter national Magnetospheric Study'. The Symposium was attended by an invited audience of 60 scientists from the ESA Member States, the United States, Japan, Canada and Austria. Following a report by the joint COSPAR-IUCSTP Special Working Group, the International Magnetospheric Study (lMS) is proposed as an international co operative enterprise of limited duration, having as its principal objective the achie vement of a comprehensive, quantitative understanding of the dynamical processes operating in the Earth's plasma and field environment. In order to accomplish this objective, it is thought to be necessary to carry out simultaneous measurements with nearly identical instrumentation at various points in space. These measurements will need to be made in combination with appropriate observations at or near the Earth's surface. Besides near-Earth observations by ground-based, rocket- and balloon-borne instrumentation, satellite investigations are expected to make an important contri bution to the IMS. A number of satellites assigned to magnetospheric research have recently been launched, or will be launched shortly, to be operational during the IMS. The European Space Agency has devoted two of its forthcoming scientific satellites - GEOS and ISEE-B - to magnetospheric and interplanetary research.

All theoretical and observational topics relevant to the understanding of the thermonuclear (Type Ia) supernova phenomenon are thoroughly and consistently reviewed by a panel including the foremost experts in the field. The book covers all aspects, ranging from the observations of SNe Ia at all stages and all wavelengths to the 2D and 3D modelling of thermonuclear flames in very dense plasmas. Scenarios for close binary evolution leading to SNe Ia are discussed. Particular emphasis is placed on the homogeneity vs. diversity of SNe Ia and on their use as standard candles to measure cosmological parameters. The book reflects the recent and very significant progress made in both the modelling of the explosions and in the observational field.

Red giant and supergiant stars have long been favorites of professional 6 and amateur astronomers. These enormous stars emit up to 10 times more energy than the Sun and, so, are easy to study. Some of them, specifically the pulsating long-period variables, significantly change their size, brightness, and color within about a year, a time scale of interest to a single human being. Some aspects of the study of red giant stars are similar to the study of pre-main-sequence stars. For example, optical astronomy gives us a tantalizing glimpse of star forming regions but to really investi gate young stars and protostars requires infrared and radio astronomy. The same is true of post-main-sequence stars that are losing mass. Optical astronomers can measure the atomic component of winds from red giant stars that are undergoing mass loss at modest rates 6 (M $ 10- M9/yr.). But to see dust grains and molecules properly, 5 especially in stars with truly large mass loss rates, ~ 10- M9/yr, one requires IR and radio astronomy. As this stage of copious mass loss only lasts for ~105 years one might be tempted to ask, "who cares?".

Even before the present Administrator of NASA, Daniel Goldin, made the phrase 'better, faster, cheaper' the slogan of at least the Office of Space Science, that same office under the Associate Administrator of Lennard Fisk and its Division of Solar System Exploration under the direction of Wes Huntress had begun a series of planetary spacecraft whose developmental cost, phase CID in the parlance of the trade, was to be held to under $150M. In order to get the program underway rapidly they chose two missions without the open solicitation now the hallmark of the program. One of these two missions, JPL' s Mars Pathfinder, was to be a technology demonstration mission with little immediate science return that would enable later high priority science missions to Mars. Many of the science investigations that were included had significant foreign contributions to keep NASA's cost of the mission within the Discovery budget. The second of these missions and the first to be launched was the Near Earth Asteroid Rendezvous mission, or NEAR, awarded to Johns Hopkins University's Applied Physics Laboratory. This mission was quite different than Mars Pathfinder, being taken from the list of high priority objectives of the science community and emphasizing the science return and not the technology development of the mission. This mission was also to prove to be well under the $150M phase CID cap.

This volume tries to summarize the status of observational knowledge of the Kuiper Belt. Its recent discovery has revitalized the astromomical study of the Solar System and is beginning to open new and unexpected windows on the physics of planetesimal accretion. With more and better observational data being obtained at the technological limit of current facilities, a new perception of the relationships that exist among the various classes of small Solar System bodies has emerged. The new observations have also motivated a number of fascinating theoretical studies in Solar System dynamics.

Since 1967, the main scientific events of the General Assemblies of the International Astronomical Union have been published in the separate series, Highlights of Astronomy. The present Volume 11 presents the major scientific presentations made at the XXIIIrd General Assembly, August 18-30, 1997, in Kyoto, Japan. The two volumes (11A+B) contain the texts of the three Invited Discourses as well as the proceedings or extended summaries of the 21 Joint Discussions and two Special Sessions held during the General Assembly.