Solar Flares

Sudden Ionospheric Disturbances resulting from an interaction of the Solar Flare radiation with the constituents of the upper atmosphere constitute one of the three major aspects of ground level monitoring of solar flares -the other two being optical observations of flares, and the observations of solar bursts in radio wavelengths. SIDs, therefore, form a major part of flare monitoring programme in many observatories. Unlike the other two, however, the ionospheric effects of flares provide one major additional source of interest - the reaction of the ionospheric plasma to an impulsive ionization. The high atmosphere provides a low pressure laboratory without walls in which a host of reactions occur between electrons, ions and neutral particles. The resulting products and their distributions may bear no resemblance to those of the primary neutral constituents or their direct ionization products. The variations with the time of the day, with season and with solar activity that form the bulk of the ionospheric measurements are too slow to allow any insight into the nature of these ionospheric reactions whose lifetimes are often very short. The relaxation time of the ionospheric ionization is only a few minutes or fraction of a minute in the lower ionosphere and in the E-region and is about 30 min to an hour at 300 km. The flares provide a sudden short impulse comparable to these time scales.

There is a force out there that could destroy our world in minutes. . . . Solar flares—brief bursts of radiation from our sun—have always existed and have never been particularly dangerous. Nature hasn’t changed. But we have. By making our world so dependent on electricity delivered by huge, unprotected power grids we have inadvertently placed humanity at terrible risk. As bestselling author Whitley Strieber explores in this urgent new work, a powerful solar flare could demolish our electrical delivery system, wiping away centuries of civilization in minutes and drastically changing our world. Such a scenario is altogether plausible—and it is the single most dangerous single thing that could happen to our civilization, more dangerous than the most massive earthquake or volcano, more dangerous than climate change, more dangerous even than nuclear war. What is worse, solar flares of a now-dangerous intensity are not all that uncommon; and not only that, our electrical and electronic infrastructure is becoming so extensive, and thus so fragile, that smaller and smaller solar flares can pose more and more serious hazards. Due to the astonishing unwillingness of power companies to cooperate, good programs that would make us safer, and that are supported by both political parties, have been routinely prevented from being enacted. In Solar Flares: What You Need to Know, Strieber reveals the dangers behind solar flares, tracks the disastrous damage they could cause, surveys what they would do to our world in the here-and-now, and explains what nations and individuals must do to prepare for them.

Solar flares are very complex electromagnetic phenomena of a cataclysmic nature. Particles are accelerated to very high velocities and a variety of physical processes happen inside and outside flares. These processes can be studied by a large number of techniques from Earth and from space. The aim is to discover the physics behind solar flares. This goal is complicated because information about the flare mechanism can be obtained only in an indirect way by studying the secondary effects. This book provides three stages in the solution of the solar flare problem. Chapter one describes the connection between observational data and theoretical concepts, where it is stressed that next to investigating flares, the related non-stationary large-scale phenomena must be studied as well. The second chapter deals with secondary physical processes, in particular the study of high-temperature plasma dynamics during impulsive heating. The last chapter presents a model built on the knowledge of the two previous chapters and it constructs a theory of non-neutral turbulent current sheets. The author believes that this model will help to solve the problem of solar flares. For solar physicists, plasma physicists, high-energy particle physicists.

A computer program has been developed which processes and groups individual observations of solar flares which describe the same feature. From each group of observations a consolidated description of the flare 'event' is produced. The report details the methods by which these groups are formed and the subsequent consolidated descriptions achieved. (Author).

The Campaign for Integrated Observations of Solar Flares (CINOF) was a period of extensive solar flare studies conducted 5-29 June 1972. Specific scientists were designated as CINOF coordinators to study selected events. This compilation contains seven reports: Five reports detailing solar phenomena associated with CINOF selected flares, one report detailing observations of a flare initiated shock wave propagating through the interplanetary medium, and one report on the solar particle and associated interplanetary measurements during this period.

The authors explore solar flares by applying physics and theoretical investigations.

This book is the first part of the originally planned publication by Z. Svestka and L. D. de Feiter 'Solar High Energy Photon and Particle Emission'. The second part, with the original title, was to be published by de Feiter in about one year from now. However, to the deep sorrow of all of us, Dr de Feiter died suddenly and unexpectedly when the present book was in print. Thus, unfortunately, de Feiter's second part may not appear. Due to the fact that the originally planned publication was divided into two parts, the present book is mainly descriptive and concerned with the flare morphology. It was expected that theoretical interpretations would be extensively developed in the second part, prepared by de Feiter. In particular, this refers to the theoretical back grounds of radio emissions, particle acceleration and particle propagation in space. Only in Chapter II, concerning the 'low-temperature' flare, do we go deeper into the theoretical interpretations, anticipating that de Feiter would have been concerned mainly with the 'high-energy' physics. Still, the book includes discussions on all important aspects of flares and thus can present the reader with a complete picture of the complex flare phenomenon. It is clear that many observed data on flares can be interpreted in different ways.