How should we do that? You would need superconducting coils on board and an extra 1000 liters of helium to cool the coils. Then run 200 Amperes through them. Y

How should we do that? You would need superconducting coils on board and an extra 1000 liters of helium to cool the coils. Then run 200 Amperes through them. You see yourself... Earths magnetic field stretches far into space. So the particles have to be diverted from their original course only a little bit. Impossible to do that for a spacecraft. Magnetic field strength decreases with 1/(r to the power of 3). In fact, for a small spacecraft, there are only a few hits into the electronics per day. I know a funny story from an astronaut, who was on the ISS for a while. He told us, even with eyes closed at "night", he could see light flashes, when a particle was absorbed within his eyeball. Nice place out there...