This volume contains the review papers presented at the International Symposium on Solar-Terrestrial Physics held at the Tavrichesky Palace, Leningrad, U.S.S.R., 11-19 May 1970. The Symposium may be regarded as the most recent member of a series of inter national symposia - for instance, the Symposium on Solar-Terrestrial Physics, Belgrade (1966), the Joint IQSY-COSPAR Symposium on Solar-Terrestrial Physics, London (1967), and the Symposium on the Physics of the Magnetosphere, Washington (1968). Like those earlier symposia, the Leningrad Symposium was sponsored by the International Astronomical Union (IAU), the International Union of Geodesy and Geophysics (IUGG), the International Union of Radio Sciences (URSI), and the ICSU Committee on Space Research (COSPAR). These bodies are all concerned with one or another aspect of solar-terrestrial physics, and all joined in believing that the time was ripe for another comprehensive symposium on all aspects of this very active field of research.

This volume contains the review papers presented at the International Symposium on Solar-Terrestrial Physics held at the Tavrichesky Palace, Leningrad, U.S.S.R., 11-19 May 1970. The Symposium may be regarded as the most recent member of a series of inter national symposia - for instance, the Symposium on Solar-Terrestrial Physics, Belgrade (1966), the Joint IQSY-COSPAR Symposium on Solar-Terrestrial Physics, London (1967), and the Symposium on the Physics of the Magnetosphere, Washington (1968). Like those earlier symposia, the Leningrad Symposium was sponsored by the International Astronomical Union (IAU), the International Union of Geodesy and Geophysics (IUGG), the International Union of Radio Sciences (URSI), and the ICSU Committee on Space Research (COSPAR). These bodies are all concerned with one or another aspect of solar-terrestrial physics, and all joined in believing that the time was ripe for another comprehensive symposium on all aspects of this very active field of research.

This volume contains the review papers presented at the International Symposium on Solar-Terrestrial Physics held at the Tavrichesky Palace, Leningrad, U.S.S.R., 11-19 May 1970. The Symposium may be regarded as the most recent member of a series of inter national symposia - for instance, the Symposium on Solar-Terrestrial Physics, Belgrade (1966), the Joint IQSY-COSPAR Symposium on Solar-Terrestrial Physics, London (1967), and the Symposium on the Physics of the Magnetosphere, Washington (1968). Like those earlier symposia, the Leningrad Symposium was sponsored by the International Astronomical Union (IAU), the International Union of Geodesy and Geophysics (IUGG), the International Union of Radio Sciences (URSI), and the ICSU Committee on Space Research (COSPAR). These bodies are all concerned with one or another aspect of solar-terrestrial physics, and all joined in believing that the time was ripe for another comprehensive symposium on all aspects of this very active field of research.

At the XV. General Assembly of the International Astronomical Union in Sydney 1973, Commission 10 for Solar Activity requested the incoming Organising Committee to establish a small group to recommend a standard nomenclature for solar features and to prepare an illustrated text which would clear the jungle of terms for the benefit of solar physicists as well as of theoreticians and research workers in related fields. The challenge was taken up by the president of Commission 10, Prof. K. O. Kiepenheuer, and his persuasive advocacy has led eventually to the present book. In the course of the work, the declared aim but not the basic purpose was revised. Rather than prepare a list of standard terms, we have preferred to collect together all the terms that appear in current English-language literature. Synonyms and partially overlapping terms are all recorded for the most part without prejudice. Each has been defined as exactly as possible with the hope that in the future they may be used and understood without ambiguity. It would be a step on the road to standardisation if these terms were not re-used for new phenomena. New observations and new theories will lead to reappraisals and redefinitions so the Glossary is intended more as a guide to the present situation than as a rule-book.