New Twists in Earth's Radiation Belts
Rings of high-energy particles encircling our planet change more than researchers realized. Those variations could amplify damage from solar storms
In 1958, an early satellite, Explorer I, made the discovery that Earth is enshrouded in belts of extraordinarily high-energy, high-intensity radiation. Now called the Van Allen belts, after the researcher who led that satellite mission, these rings are known to wax and wane in intensity, for reasons that are still being investigated. Satellites now criss-cross these belts, so understanding what influences them has dire implications for communications and other technologies in our modern age. Solar storms and space weather can pump them up, making the radiation zones around Earth immensely more dangerous for days or even weeks on end. The author has been involved with instruments on the dual Radiation Belt Storm Probes satellites that were launched on August 30, 2012, into Earth orbit to study the two known Van Allen belts, and the team was lucky to catch a large solar flare a few days after launch. Amazingly, the particles impacted by this solar storm settled into a new configuration, showing an extra, temporary third belt between the other two. This new research shows that the belts can reconfigure their structure and density quickly, on the range of seconds to hours. Other observed events are showing researchers the interplay between the belt’s own internal magnetic acceleration of particles and the influx of energy from space weather. The results may not only help to protect satellites but can also be extrapolated to understand what’s happening on other planets inside and outside our Solar System.
Go to Article