Ion thrusters are a type of electric propulsion system used in spacecraft. They work by ionizing a propellant, usually a gas like xenon, and then using electric fields to accelerate the ions, creating thrust. This method is highly efficient, allowing spacecraft to travel long distances with less fuel compared to traditional chemical rockets. These thrusters produce a small amount of thrust over a long period, making them ideal for deep-space missions. For example, the Dawn spacecraft used ion propulsion to explore the asteroid belt, demonstrating the technology's effectiveness in reaching distant targets while conserving fuel.