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Polar cap boundary layer waves are ELF/VLF electric and magnetic waves detected on field lines just adjacent to the polar cap. Intense waves are present at this location essentially all (96%) of the time.

A dawn/dusk flank auroral event has been studied using multiple observations of the WIND and POLAR spacecraft, Antarctic all-sky images and Greenland magnetometers.

The Cassini spacecraft flew past the Earth in a trajectory almost along the Sun-Earth line, giving a unique perspective of low frequency waves in geospace.

We statistically analyze many interplanetary shock events where there are both WIND interplanetary data and POLAR UV imaging data. We find that the shock compression events trigger pseudobreakups (PBs), substorm onsets, or enhance (pre-existing) substorm intensities. Using WIND interplanetary data and ground-based data, it is now believed that we can predict when PBs will occur and when substorm expansion phases will occur.

Ten interplanetary WIND shock/ pressure pulse events are used to study the magnetospheric delay of pseudobreakup (PB) or substorm onsets. We identify the PBs and substorms by using the POLAR UV imaging data. The states of the interplanetary medium and the conditions of the ionosphere before and after the auroral brightening onsets are studied. We find that the magnetospheric delay time strongly constrains the location of the nightside X-line during such events. We also find for PB (or no activity) events, that the interplanetary and ionosphere preconditions are unusually low.

We find that small (10-200 rP) magnetic decreases comprise a dominant part of the polar solar wind microstructure at Ulysses distances (2.2 AU). These magnetic field dips are almost always bounded by tangential discontinuities, a feature which is not well understood at this time. Hundreds of these events have been examined in detail and a variety of types have been found. These will be described. It is speculated that these structures have been generated by perpendicular heating of ions closer to the Sun and have then been convected to distances of Ulysses. Such structures may be very important for the rapid cross- field diffusion of ions in the polar regions of the heliosphere.

We report four different types of plasma waves detected in the near the dayside polar cap boundary layer (PCBL) region at high altitudes (>6 R***sub E***).

In this paper we examine the causes of largest magnetic storms at Earth (as measured by Dst). Possible interplanetary mechanisms for the creation of very intense magnetic storms are discussed.

The January 10, 1997 interplanetary pressure pulse (observed at 0053 UT at Wind) caused a dayside aurora, as seen in Polar Ultraviolet Imager (UVI) data, that propagates tailward and to lower L.

The purpose of this paper is to study an interplanetary Bs feature ahead of a magnetic cloud and its related auroral and magnetospheric responses.

A review of the Interplanetary causes of geomagnetic activity is presented.

We examine possible interplanetary mechanisms for the Creation of the largest magnetic storms at the Earth.

The full Jovian magnetopause boundary layer (BL) plasma wave spectra from 10(sup -3) to 10(sup 3) Hz, have been measured for the first time...The B'/E' ration does not have a f(sup -1) dependency, so it was suggested that the waves are a mixture of whistler mode electromagnetic emissions and electrostatic waves.

Large amplitude, noncompressive Alfven waves and rotational discontinuities are shown to be arc-polarized. The slowly rotating Alfven wave portion plus the fast rotating discontinuity comprise 360(deg) in phase rotation. The magnetic field vector perturbation lies in a plane. There are two (or more) possible interpretations to the observations.

A model/theory for the Jovian aurora is formed based on a similar model for the dayside aurora at Earth and recent Ulysses field and particle measurements at Jupiter. Items discussed are plasma boundary layer, wave-particle resonant interactions, and the model's prediction of the aurora's location, latitudinal width, and intensity.

This presentation examines the magnetic field fluctuations within Corotating Interaction Regions (CIRs) detected by Ulysses at mid- and low-latitudes. CIRs are formed by the interaction of high-speed streams flowing from the polar coronal hole with slow-speed streams. Several wave modes are identified, and the effectiveness of these waves causing magnetic storms at Earth will be discussed.

Data from the Ulysses spacecraft was used for studying solar tangential discontinuities (TDs) at high latitudes. Significant numbers of TDs seem to exist at these latitudes.

Interplanetary magnetic field and plasma data are compared with ground-based geomagnetic Dst and AE indices to determine the causes of magnetic storms, substorms, and quiet during the descending phase of the solar cycle. The primary focus is on 1974 data characterized by the presence of two long-lasting corotating streams associated with coronal holes.

The rate of occurrence of interplanetary discontinuities (ROID) is examined using Ulysses magnetic field and plasma data from 1 to 5 AU radial distance from the Sun and at high heliographic latitudes. We find two regions where the ROID is high: in stream-stream interaction regions and in Alfven wave trains. This latter feature is particularly obvious at high latitudes when Ulysses enters a high speed stream associated with a polar coronal hole. These streams are characterized by the presence of continuous, large-amplitude (Delta (vector 13)/absolute value of B is about 1-2 Alfven waves and an extraordinarily high ROID value (approximately 150 discontinuities/day). In a number of intervals examined, it is found that (rotational) discontinuities are an integral part of the Alfven waves. The nonlinear Alfven waves are spherically polarized, i.e., the tip of the perturbation vector resides on the surface of a sphere (a consequence of constant absolute value of B). The slowly rotating part of the wave rotates approximately 270 deg in phase. There is a slight arc in the B(sub 1) - B(sub 2) hodogram, suggesting an almost linear polarization. The phase rotation associated with the discontinuity is about 90 deg, lies in the same plane as the slowly rotaing part of the Alfven wave, and therefore completes the 360 deg phase rotation. The best description of the overall Alfven wave plus discontinuity is a spherical, arc-polarized, phase-steepened wave.