I hope all is well.
References for you: attached.
Ion engines: these engines can accomplish missions that are impossible with traditional chemical propulsion. Saying that ion propulsion is only used for satellites is not quite right. Ion propulsion has been used in interplanetary space (see attached articles). Ion propulsion has revolutionized all of space exploration.
NASA John H. Glenn Research Center
Cleveland, OH 44135
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Fuels and Space Propellants Web Site: