The aim of this book is to describe and discuss the aurora as an optical phenomenon, one which can be observed by the naked eye as well as with more sensitive optical detectors. It continues the tradition of study ing that impressive and imaginative play of nature, the northern lights, seen and discussed by the Greek philosphers as early as the sixth century B.c. Today the study of the optical aurora is only one of many ways of acquiring information about a major phenomenon: the ejection of plasma from the sun, the interaction of this plasma with the geomagnetic field and the injection of...

On attending a conference on the Jovian satellites at UCLA, I heard Lou Lanze rotti vigorously present the exciting data on the sputtering of water ice by Me V protons taken with W. L. Brown at AT&T Bell Labs. In his inimitable way he made clear that this new electronic sputtering process was very poorly under stood and was very important for surface properties of sattelites. I was immedia tely hooked, and have been working ever since with Lanzerotti, Brown, my col league at Virginia, John Boring, and Bo Sundqvist at Uppsala on understanding the ejection of material from surfaces and applying...

This book presents a review of those efforts that have been and are being made to determine the geochemical composition of the moon and planets. The authors have attempted to present both a review as well as their philosophy about the development of flight experiments for geo chemical studies. Their basic premise is that such flight experiments should emphasize the scientific objectives and a total systems approach to meeting these objectives, involving the analytical device, data handling and data interpretation. While the above seems reasonably obvious, many proposals of experiments often...

Since the discovery of geomagnetically trapped radiation by Van Allen in 1958, an impressive amount of experimental information on the earth's particle and field environment has nourished research work for scores of scientists and thesis work for their students. This quest has challenged space-age technology to produce better and more sophisticated instru ments and has challenged the international scientific community and governments to establish more, and more effective, cooperative programs of research and information exchange. As a result, an orderly picture of the principal physical...

Little more than ten years have passed since spaceprobe-borne instruments con clusively demonstrated the existence of the solar wind. These observations con firmed the basic validity of a theoretical model, first proposed by E. N. Parker, predicting a continuous, rapid expansion of the solar corona. The subsequent decade has seen a tremendous growth in both the breadth and sophistication of solar wind observations; the properties of the interplanetary plasma near the orbit of the earth are now known in great detail. The theory of the coronal ex pansion has also been highly refilled both in...

Although there are, in addition to the classic but somewhat dated books'l-, some excellent recent books on ionospheric physics and aeronomy'l-..., their scope is quite different from that of the present monograph. This monograph concentrates on the fundamental physical and chemical processes in an idealized planetary ionosphere as a general abstraction, with actual planetary ionospheres representing special cases. Such an approach appears most appropriate for a concise in troduction to the field, at a time when increasing experimental in formation on the ionospheres of other planets can be...

The advent of artificial earth satellites in 1957-58 opened a new dimension in the field of geophysical exploration. Discovery of the earth's radiation belts, consisting of energetic electrons and ions (chiefly protons) trapped by the geomagnetic field, followed almost immediately 1,2]' This largely unexpected development spurred a continuing interest in magnetospheric exploration, which so far has led to the launching of several hundred carefully instrumented spacecraft. Since their discovery, the radiation belts have been a subject of intensive theoretical analysis also. Over the years, a...

In recent years the significant progress in satellite-based observations of plasma states and associated electromagnetic phenomena in space has resulted in the accumulation of much evidence of various plasma instabilities. Today plasma instabilities are believed to be responsible for electromagnetic radiation as well as for many of the macroscopic dynamics of plasmas in space. Most students who begin to study plasma physics are intrigued by the unstable nature of plasmas compared with other states of matter; however, they often become frustrated because there are so many in stabilities. Such...

The study of very long-distance and around-the-world propagation of HF radio waves becomes more urgent in connection with the problems of long distance ground-based radio communications, communications with space crafts and satellites, satellite-to-satellite communications, around-the-world radar scanning, around-the-world sounding of the ionosphere, etc. At pre sent, these investigations have acquired particular interest because transmit ters which make it possible to intentionally modify the ionospheric properties by powerful radio waves have become available. In the case of radio wave...

The experimental study of magnetospheric processes consists of several disci plines or methods, developing in two general directions. The first, internal trend covers the progress in experimental techniques and methods and re search specific to this discipline. The other trend combines with other methods in a mutual attempt at understanding the boiling whirlpool of the disturbed magnetosphere. Investigations of auroral X-rays began after Van Allen's (1957) discovery of hard radiation in the upper atmosphere of the auroral zone, and are based on high latitude balloon observations. Scientific...