How do particles move in a magnetic field in space?

A moving charged particle in a magnetic field feels the Lorentz force, which pushes it perpendicular to both its velocity and the field direction. That sideways push makes the particle curve into a circular or helical path. In space, this is why electrons and protons can become trapped in regions such as Earth’s radiation belts. Magnetic fields around planets and stars can guide particles for vast distances. This behavior is fundamental to plasma physics and helps explain auroras, solar storms, and cosmic rays.