Carl Stormer

 

Carl Stormer was born in Norway in 1874 and became a world-renound authority on aurora. Until his death in 1957, he was a professor at the Institutt for Teoretisk Astrofysikk in Blindern, Norway.

He pioneered the technique of using photography to capture images of aurora for closer study. He and his colleagues set up 20 observatories in Norway to produce over 40,000 photographs of all stages in the development of aurora. In 1910 he used triangulation methods to determine how far above the ground that aurora occur - typically 100 kilometers. Stormer proposed that aurora are produced when powerful storms on the sun blast particles at Earth which flow down into the polar regions along lines of magnetism. As it would later turn out, this explanation is quite wrong, however it still remains the most cited explanation found in common textbooks!

In 1930, Stormer published a research paper "Twenty-five Years' York on the Polar Aurora," in the science journal Terrestrial Magnetism and Atmospheric Electricity (volumn 35 page 193). His paper sought to find an explanation for the origin of the still-mysterious aurora. What he found in his mathematical throry, was that when particles from the sun collide with Earth's magnetic field, they would be deflected from the equatorial regions into the polar regions of Earth. Could this be the flow of particles that caused aurora? He thought so. But there was more to be discovered in the complex equations than just an explanation for aurora.

His calculations also showed how there would be some regions around Earth where the particles could not penetrate. Stormer called them Forbidden Regions, but this would only be true for particles trying to enter from the outside. For particles already in these regions, they would become trapped. Just before van Allen's discoveries of these 'trapped particles' a physicist S. Fred Singer had used some of Stormer's ideas to uncover this possibility. In his article, "A New Model of Magnetic Storms," published in 1957 in the prestigeous Transactions of the American Geophysical Union (volume 38 page 175), he suggested that these clouds of trapped particles might be found in space.