Summary

Abstract

This paper is intended as a coherent summary of the topics and results covered at this Workshop, of the questions that have been answered (or else have not been answered) and of the controversies that still remain, to be presented in a rather broad-brush fashion (“stich-wortartig” as one says in German); detailed presentations are to be found in the individual papers of this volume. It is natural, in doing this, to compare the status of polar cusp studies at this Workshop with previous meetings devoted to the subject, in particular with the first magnetospheric cleft symposium held in Dallas in 1973 for which I also published a summary (Vasyliunas, 1974). The most immediately apparent result of such a comparison is that enormous amounts of additional data, and qualitatively new data as well, on the polar cusp have become available in the 11 years since the Dallas symposium. With the new data, inevitably, many new questions arise; of the old questions — those that were the maini topic of discussion at Dallas — there are important ones that still remain unanswered and some that have received a clear answer. It becomes clearer at each successive meeting that the polar cusp is not an isolated topic but one that has close connections to many other aspects of magnetospheric physics; several presentations did not deal directly with the cusp but were nevertheless obviously relevant to the subject of the Workshop.