The Heliosphere Near Solar Minimum


Book Description

On the Ulysses mission scientists gathered observations from the unexplored regions of the heliosphere. This book presents a highly readable and concise account of the results. The authors summarise our understanding of the area and provide the basis for understanding the more complex state of the heliosphere around solar maximum. The first chapter provides an overview of the region, introducing the heliosphere prior to the Ulysses mission, and mission objectives. Subsequent chapters discuss the areas of the heliosphere, large and small scale features, cosmic rays and energetic particles, and the observations of interstellar gas and cosmic dust.




Solar and Space Physics


Book Description

In 2010, NASA and the National Science Foundation asked the National Research Council to assemble a committee of experts to develop an integrated national strategy that would guide agency investments in solar and space physics for the years 2013-2022. That strategy, the result of nearly 2 years of effort by the survey committee, which worked with more than 100 scientists and engineers on eight supporting study panels, is presented in the 2013 publication, Solar and Space Physics: A Science for a Technological Society. This booklet, designed to be accessible to a broader audience of policymakers and the interested public, summarizes the content of that report.




Solar Dynamics and its Effects on the Heliosphere and Earth


Book Description

This volume helps the reader to understand the ways and means of how dynamical phenomena are generated at the Sun, how they travel through the Heliosphere, and how they affect Earth. It provides an integrated account of the three principal chains of events all the way from the Sun to Earth: the normal solar wind, coronal mass ejections, and solar energetic particles.




Cosmic Winds and the Heliosphere


Book Description

Contributors examine the physics of wind origin and physical phenomena in winds, including heliospheric shocks, magnetohydrodynamic turbulence, and kinetic phenomena--and their interactions with surrounding media. Contributions range from studies of the interstellar cloud surrounding the solar system to solar wind interaction with comets.




The Heliosphere in the Local Interstellar Medium


Book Description

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.




The Heliosphere through the Solar Activity Cycle


Book Description

Understanding how the Sun changes though its 11-year sunspot cycle and how these changes affect the vast space around the Sun – the heliosphere – has been one of the principal objectives of space research since the advent of the space age. This book presents the evolution of the heliosphere through an entire solar activity cycle. The last solar cycle (cycle 23) has been the best observed from both the Earth and from a fleet of spacecraft. Of these, the joint ESA-NASA Ulysses probe has provided continuous observations of the state of the heliosphere since 1990 from a unique vantage point, that of a nearly polar orbit around the Sun. Ulysses’ results affect our understanding of the heliosphere from the interior of the Sun to the interstellar medium - beyond the outer boundary of the heliosphere. Written by scientists closely associated with the Ulysses mission, the book describes and explains the many different aspects of changes in the heliosphere in response to solar activity. In particular, the authors describe the rise in solar activity from the last minimum in solar activity in 1996 to its maximum in 2000 and the subsequent decline in activity.




Cosmic Rays in the Heliosphere


Book Description

In every scientific discipline there are milestones - periods of significant accom plishment when it is appropriate to pause and summarize the state of the field. Such is the case for the study of the behavior of cosmic rays in the heliosphere. We are just passing through solar minimum conditions, when the heliosphere has a well-ordered and relatively simple configuration. We have been fortunate to have an array of spacecraft - unprecedented in the history of space exploration and unlikely to be repeated for generations - to provide comprehensive measurements of cosmic rays throughout the heliosphere. Ulysses has completed its historic first exploration of the heliosphere at high heliographic latitudes. Pioneer and Voyager have been exploring the outer heliosphere. The durable IMP-8 and now the WIND spacecraft have provided detailed baseline measurements at Earth. Concurrently, there has been a steady improvement in theoretical understanding of cosmic ray behavior through the use of ever more sophisticated numerical models. This milestone in cosmic ray studies was celebrated with a Workshop on Cos mic Rays in the Heliosphere which was convened by L. A. Fisk, J. R. Jokipii.




Interstellar Boundary Explorer (IBEX)


Book Description

over to nominal operations and began making our groundbreaking science observations. Remarkably, the IBEX project was able to do all this work including developing an entirely new launch capability, building and ying a unique and highly specialized spacecraft and instrument suite, and maintaining full funding for our Education and Public Outreach and Phase E science activities, while still under-running our original cost cap (as modi ed by NASA-directed changes), by roughly three-quarters of a million dollars. This book comprises a set of papers that describe the IBEX science, instruments, and mission and put these in the context of the existing knowledge of the interstellar interaction at the time of the launch. The book sets the stage for research that will be based on data from the IBEX mission. We sincerely hope that future researchers, authors and students will use this information to help in their studies. Chapter 1 [McComas et al. ] provides an overview of the entire IBEX program including the IBEX science, hardware, and mission. Chapter 2 describes the IBEX spacecraft and ight system [Scherrer et al. ]. Chapters 3–4 provide the details of the IBEX-Hi instrument [Funsten et al. ] and background monitor that is built into it [Allegrini et al. ], while Chapters 5–7 describe the IBEX-Lo instrument [Fuselier et al. ], how IBEX-Lo can measure the interstellar neutrals directly entering the heliosphere [Möbius et al.




The Sun, the Solar Wind, and the Heliosphere


Book Description

This volume represents the state of the art of the science covered by the International Association of Geomagnetism and Aeronomy (IAGA) Division IV: Solar Wind and Interplanetary Field. It contains a collection of contributions by top experts addressing and reviewing a variety of topics included under the umbrella of the division. It covers subjects that extend from the interior of the Sun to the heliopause, and from the study of physical processes in the Sun and the solar wind plasma to space weather forecasts. The book is organized in 6 parts: the solar interior, the solar atmosphere, the heliosphere, heliophysical processes, radio emissions, and coordinated science in the Sun-Earth system. In addition, we highlight some of the results presented during the IAGA Division IV symposia in the 11th Scientific Assembly of IAGA in Sopron, Hungary, on 23-30 August 2009, which was planned simultaneously with this book.




The Maunder Minimum and the Variable Sun-earth Connection


Book Description

An excursion through solar science, science history and geoclimate with a husband and wife team who revealed some of our sun's most stubborn secrets.