How does solar electric propulsion (ion propulsion) work?Solar electric propulsion takes advantage of magnetism and electricity to push a ship through space. Electricity, generated by the ship's solar panels, gives a positive electrical charge to atoms inside the chamber. They are pulled by magnetism towards the back of the ship and then pushed by magnetic repulsion out of the ship. (This is like what happens when you hold the same pole of two different magnets close to each other. They repel each other.) This steady stream of atoms going out of the spacecraft gives it the thrust it needs to go forward through space.
Courtesy of Northwestern University