According to our manner of looking at the matter, every star in the universe would be the seat and field of activity of electric forces of a strength that no one could imagine. We have no certain opinion as to how the assumed enormous electric currents with enormous tension are produced, but it is certainly not in accordance with the principles we employ in technics on the earth at the present time. One may well believe, however, that a knowledge in the future of the electrotechnics of the heavens would be of great practical value to our electrical engineers. It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. We have assumed that each stellar system in evolutions throws off electric corpuscles into space. It does not seem unreasonble therefore to think that the greater part of the material masses in the universe is found, not in the solar systems or nebul\ae, but inempty" space.

So wrote Kristian Birkeland in the Norwegian Aurora Polaris Expedition 1902-1903, Christiana, Norway, Aschehoug, Secs. 1 and 2, 1908, 1913.

The year 1996 marked the Centennial Celebration of the founding of Plasma Astrophysics and Cosmology; its origins may be traced to the seminal research of Kristian Birkeland published in 1896 that began his life--long study of laboratory produced cathodic rays and corpuscles\footnote{The term plasma' was not to be coined by I. Langmuir until 1923.} and their analogies to astrophysical and cosmological phenomena. This work was presented in two papers: Sur un spectre des rayons catodiques" in {\em Comptes Rendus}, 28 September 1896, and a paper in {\em Archives des Sciences Physiques et Naturelles}, Geneva, 4th period, vol. I, 1896, that announced his discovery of magneto--cathode rays. It was in this work that, according to Birkeland (1908): \begin{quote} \ldots I expressed for the first time my belief that the northern lights are formed by corpuscular rays drawn in from space, and coming from the sun. \end{quote} In addition to his solving the mystery of the Aurora with his now--famous terrella experiments; electron beams in vacuum from magnetized copper globe cathodes, Birkeland utilized his data to formulate a theory about a plasma--filled universe populated with {\em systems} of nebula (galaxies). }: Un fait qui frappe tout le monde, c'est la forme spirale de certaines n\'ebuleuses; elle se rencontre beaucoup trop souvent pour qu'on puisse penser qu'elle est due au hasard. On comprend combien est incompl\ete toute th\'eorie cosmogonique qui en fait abstraction. Or aucune d'elles n'en rend compte d'une mani\ere satisfaisante, et l'explication que j'ai donn\'e moi-m\eme un jour, par maini\ere de passe--temps, ne vaux pas mieux que les autres. Nous ne pouvons donc terminer que par un point d'interrogation." \end{quote} \begin{figure} \vspace{15cm} \caption{Kristian Birkeland.} \label{figure1} \end{figure} Much of Birkeland's work was rediscovered in the 1980s with renewed interest about the role of large scale magnetic fields and currents in explaining astrophysical, galactic, and cosmological scale phenomena, including the origin and structure or galaxies and the containment of intergalactic gas clouds' and filaments, formerly attributed to dark matter gravitational binding energy. While the study of plasma phenomena in astrophysics and cosmology is now a century old, plasma--based theories for the explanations of light element abundances, the cosmic microwave background, and the origin of large--scale structures are relatively recent topics but have rapidly developed since their introduction at the first IEEE International Conference on Plasma Cosmology, La Jolla, California, USA, 20--22 February 1989 (IEEE, 1990).