Our planet is nestled in the center of two immense, concentric doughnuts of powerful radiation: the Van Allen radiation belts, which harbor swarms of charged particles that are trapped by Earth's magnetic field. On March 17, 2015, an interplanetary shock - a shockwave created by the driving force of a coronal mass ejection, or CME, from the sun - struck Earth's magnetic field, called the magnetosphere, triggering the greatest geomagnetic storm of the preceding decade. And NASA's Van Allen Probes were there to watch the effects on the radiation belts.
↧