The subject of this volume in the Astrophysics and Space Science Library is Electro magnetic Radiation in Space. It is essentially based on the lectures given at the third ESRO Summer School which was held from 19 July to 13 August, 1965, in Alpbach, Austria. Fifty-eight selected students attended the courses representing the following countries: Austria (2), Belgium (1), Denmark (1), France (12), Germany (10), Italy (7), Netherlands (2), Spain (4), Sweden (6), Switzerland (3), United Kingdom (9), United States (1). Thirteen lectures courses and nine seminars were given by sixteen different scientists in total. In this book the courses and seminars have been classified in three parts according to the kind of radiation which they mainly deal with: Ultraviolet Radiation, X Radiation and Cosmic Radiation. These parts can be broken down further in theo retical and observational aspects, whereas in the first and second part solar as well as stellar ultraviolet- and X-radiation can be distinguished. * Due to various reasons the publication of this volume had to be delayed; it was therefore judged appropriate to bring the text up to date. The various lecturers have been asked to revise the manuscripts and to eventually add new information which has been acquired in this rapidly evolving field of space astrophysics. Most authors have responded positively to this request, some even have completely rewritten the manuscript.

Active remote sensing is the principal tool used to study and to predict short- and long-term changes in the environment of Earth - the atmosphere, the oceans and the land surfaces - as well as the near space environment of Earth. All of these measurements are essential to understanding terrestrial weather, climate change, space weather hazards, and threats from asteroids. Active remote sensing measurements are of inestimable benefit to society, as we pursue the development of a technological civilization that is economically viable, and seek to maintain the quality of our life. A Strategy for Active Remote Sensing Amid Increased Demand for Spectrum describes the threats, both current and future, to the effective use of the electromagnetic spectrum required for active remote sensing. This report offers specific recommendations for protecting and making effective use of the spectrum required for active remote sensing.

Electromagnetic (EM) waves carry energy through propagation in space. This radiation associates with entangled electric and magnetic fields which must exist simultaneously. Although all EM waves travel at the speed of light in vacuum, they cover a wide range of frequencies called the EM spectrum. The various portions of the EM spectrum are referred to by various names based on their different attributes in the emission, transmission, and absorption of the corresponding waves and also based on their different practical applications. There are no certain boundaries separating these various portions, and the ranges tend to overlap. Overall, the EM spectrum, from the lowest to the highest frequency (longest to shortest wavelength) contains the following waves: radio frequency (RF), microwaves, millimeter waves, terahertz, infrared, visible light, ultraviolet, X-rays, and gamma rays. This Special Issue consists of sixteen papers covering a broad range of topics related to the applications of EM waves, from the design of filters and antennas for wireless communications to biomedical imaging and sensing and beyond.

Examines how solar and terrestrial space phenomena affect sophisticated technological systems Contemporary society relies on sophisticated technologies to manage electricity distribution, communication networks, transportation safety, and myriad other systems. The successful design and operation of both ground-based and space-based systems must consider solar and terrestrial space phenomena and processes. Space Weather Effects and Applications describes the effects of space weather on various present-day technologies and explores how improved instrumentation to measure Earth's space environment can be used to more accurately forecast changes and disruptions. Volume highlights include: Damage and disruption to orbiting satellite equipment by solar particles and cosmic rays Effects of space radiation on aircraft at high altitudes and latitudes Response of radio and radar-based systems to solar bursts Disturbances to the propagation of radio waves caused by space weather How geomagnetic field changes impact ground-based systems such as pipelines Impacts of human exposure to the space radiation environment The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals. Find out more about the Space Physics and Aeronomy collection in this Q&A with the Editors in Chief

Vols. 34- include section: Waves and electrons.

The material given in this 'Introduction to astronomical photometry' is the subject matter of a lecture at the University of Geneva. It is, therefore, intended for those students, physicists or mathematicians, who have completed their bachelor's degree or diploma, and are intending to work for their Ph.D. in astronomy. We assume then the elementary ideas of astrophysics, magnitude, colour index, spectral classes, luminosity classes, gradient, atmospheric extinction are already known. The student may find it useful to re-read the work of Schatzman [1], Dufay [2] and Aller [254] before embarking upon the study of this 'Introduction to astronomical photometry'. It is not our aim in this book to deal with every aspect of stellar photometry. On the contrary, we shall restriet ourselves to looking at subjects ofwhich knowledge seems to us essential for someone who has to use photometrie quantities in his astronomical research. We are, therefore, keeping the interests of the photometrie measurements user partieularly in mind. We shall only discuss very superficially the technical prob lems and reduction methods for atmospheric extinction. These problems are dealt with very clearly in Astronomical Techniques [3]; the first by A. Lallemand, H. L.