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The quadrennium 1979–1982 witnessed notable advances in magnetospheric and interplanetary physics and demonstrated some major trends. Examples of both will be listed below, followed by an evaluation of the state of the discipline and of its future.

Standing out among the advances is the enormous volume of data about the magnetospheres of the giant planets collected by Voyagers 1–2 and by Pioneer 11. At the start of 1979 the very existence of Saturn's magnetic field was uncertain, and the role of the satellite Io in Jupiter's magnetosphere was only dimly guessed. Four years later we have extensive information on both magnetospheres, on their underlying planetary fields, ring currents, radio emissions, plasma composition, and nightside configuration, and about such matters as Io's plasma torus and the current filament linking Io to Jupiter, Saturn's inner radiation belt (from neutron albedo), and Titan's wake.

During the same interval great strides were also made toward tracing the behavior of different ion species in the earth's magnetosphere, charting the variability of different ions, and deducing their sources. The effort included widespread international collaboration, with key observations coming from European experiments. Much has been learned, but the data must still be extended to the 20–200 keV energy range, where most of the energy resides. Details have also come to light about the global distribution of ‘beams’ and ‘conies,’ and about the relative abundances of O+, He+, He++, H+ and O+ +. Further properties of field-aligned voltage drops have been noted, including a suggestion of very narrow electric field structures, observable only with a millisecond time resolution.