ABSTRACT

The Earth’s magnetosphere is, as we saw in Chapter 2, the region of space dominated by the Earth’s magnetic field and its contained plasma. The magnetosphere completely surrounds the Earth and forms its outermost environment. We saw how charged particles behave in its static or quasi-static electric and magnetic fields. We noted, though, that the magnetosphere is, in reality, a highly dynamic, constantly changing environment within which timevarying electric fields prevail and have the ability to accelerate charged particles. We do not yet have a reliable picture of the magnetosphere as a whole. Our grasp of the structure, content and changes has had to be assembled from isolated spot measurements from spacecraft pursuing a variety of orbits.