Abstract Knowledge of the ion composition in the near-Earth's magnetosphere and plasma
sheet is essential for the understanding of magnetospheric processes and instabilities. The …

This paper reviews our current understanding of auroral features that appear poleward of
the main auroral oval within the polar cap, especially those that are known as Sun-aligned …

We discuss, in a limited way, some of the challenges to advancing our understanding and
description of the coupled plasma and neutral gas that make up the ionosphere and …

This paper reviews the state of knowledge concerning the source of magnetospheric plasma
at Earth. Source of plasma, its acceleration and transport throughout the system, its …

A distinct class of aurora, called transpolar auroral arc (TPA)(in some cases called “theta”
aurora), appears in the extremely high-latitude ionosphere of the Earth when interplanetary …

One of the longstanding questions of space science is: How does the Earth's
magnetosphere generate auroral arcs? A related question is: What form of energy is …

Based on in situ and ground‐based observations, a new type of “polar cap hot patch” has
been identified that is different from the classical polar cap enhanced density structure (cold …

This chapter reviews recent findings of multi‐scale structures and dynamics in the high‐
latitude ionosphere, particularly on meso‐scale (10s‐100s km) processes, as well as their …

The manner in which the Earth's magnetosphere responds to the solar wind is highly
dependent upon the orientation of the interplanetary magnetic field (IMF), particularly the …

Polar cap arcs are often called sun-aligned arcs. Satellite observations reveal that polar cap
arcs join together at the cusp and are actually cusp aligned. Strong ionospheric plasma …