What are the advantages of ion engines?
Ion engines are very efficient: they deliver about ten times as much ‘impulse’ per kilogram of propellant used. This allows a substantial reduction of the mass of the fuel carried on the spacecraft, which in turn leaves more room — more weight — for scientific instrumentation. Also, ion engines allow designing trajectories to travel very long distances in less time, thereby opening the door to a deeper space exploration. Another advantage is that these engines allow very accurate spacecraft control, which is essential for missions that require highly precise target pointing.
