Akira Hasegawa & Tetsuya Sato 
Space Plasma Physics [PDF ebook] 
1 Stationary Processes

During the 30 years of space exploration, important discoveries in the near-earth environment such as the Van Allen belts, the plasmapause, the magnetotail and the bow shock, to name a few, have been made. Coupling between the solar wind and the magnetosphere and energy transfer processes between them are being identified. Space physics is clearly approaching a new era, where the emphasis is being shifted from discoveries to understanding. One way of identifying the new direction may be found in the recent contribution of atmospheric science and oceanography to the development of fluid dynamics. Hydrodynamics is a branch of classical physics in which important discoveries have been made in the era of Rayleigh, Taylor, Kelvin and Helmholtz. However, recent progress in global measurements using man-made satellites and in large scale computer simulations carried out by scientists in the fields of atmospheric science and oceanography have created new activities in hydrodynamics and produced important new discoveries, such as chaos and strange attractors, localized nonlinear vortices and solitons. As space physics approaches the new era, there should be no reason why space scientists cannot contribute, in a similar manner, to fundamental discoveries in plasma physics in the course of understanding dynamical processes in space plasmas.