GREENBELT, Md., July 26 (UPI) -- A massive, natural particle accelerator exists in the Van Allen radiation belts, a region of super-energetic particles surrounding Earth, U.S. scientists say.
Results from NASA's Van Allen Probes mission show the acceleration energy is in the belts themselves, as local variations in energy levels kick particles inside the belts to ever-faster speeds approaching 99 percent of the speed of light, the space agency reported Thursday.