The space high above Earth may seem empty, but it’s a carnival packed with magnetic field lines and high-energy particles. This region is known as the magnetosphere and, every day, charged particles put on a show as they dart and dive through it. Like tiny tightrope walkers, the high-energy electrons follow the magnetic field lines. Sometimes, such as during an event called magnetic reconnection where the lines explosively collide, the particles are shot off their trajectories, as if they were fired from a cannon.