Earth’s magnetic field protects the planet from the Sun’s hot, fast wind. Diverted by the field, the charged particles that make up the wind fly past Earth into interplanetary space. But plenty of them leak through, and some are trapped. Like mosquitoes on the inside of a mosquito net, trapped particles can be particularly irksome.
Indeed, the swarm of high-energy particles held in Earth’s two radiation belts can damage, even destroy, the control systems, sensors, and solar cells of orbiting spacecraft. Although the slot between the radiation belts provides an orbital haven for satellites, orbits are typically chosen to maximize mission effectiveness, not to minimize radiation damage.
Besides, strong solar storms can change the size and location of the radiation belts. Spacecraft therefore require shielding not only against harsh prevailing conditions but also against severe rare storms.
No solar storm, however, has jolted Earth’s inner radiation belt more than the...
