Recent observations by NASA’s twin Van Allen Probes show that a local kick of energy accelerates particles in the radiation belts surrounding Earth. The readings help explain how these particles reach energies of 99 percent the speed of light. Image Credit: G. Reeves/M. Henderson
I was in knee pants when I first heard about the Van Allen radiation belts, the donut-shaped rings of charged particles circling the Earth. In the movie (and later television series), “Voyage to the Bottom of the Sea” the belts catch fire, threatening the planet with global warming at hyperspeed – an impossible apocalypse.
The belts were new and little explored then, and one of my siblings told me they were named for their discoverer, James Van Allen, a University of Iowa physicist and a born and bred Iowan. In typical chip-on-the-shoulder Iowa fashion (“Hey, we’re more than corn! We have scientists!”), I’ve been proud of that discovery and its name ever since.
Van Allen’s research brought prestige and fame to U of I’s physics department and attracted some top scientists. And almost 60 years after the belts’ discovery, the university’s research still yields new insights.
The latest, published last month, shows the belts act as a potent particle accelerator, pushing electrons to nearly light speed.
Iowa Science Interface 