Ion propulsion is a type of spacecraft propulsion that uses ions, or charged particles, to generate thrust. It works by accelerating these ions through electric fields, which creates a stream of ions that pushes the spacecraft in the opposite direction. This method is highly efficient, allowing spacecraft to travel long distances with less fuel compared to traditional chemical rockets. One of the most notable uses of ion propulsion is in the Dawn spacecraft, which explored the asteroids Vesta and Ceres. Ion propulsion systems can operate for extended periods, making them ideal for deep space missions where conventional propulsion would be less effective.