Engineering360: "Electric Spacecraft Propulsion: How Do Ion Thrusters Work?"

Why don't we just use what the gov, etc. learned from downed alien space craft ? Rather than wasting time and money on old engineering ! The gov, and NASA ,etc. hides every thing from us like we are just dumb sheep !

Well said! Probably because their black budget is so expensive they dare not admit to its existance---never mind releasing advanced tech from within.

Perhaps there will be more than three types of electric propulsion in the future?
http://www.bestsyndication.com/072407_solar-power-sailing-in-outer-space-extend-long-distance-travel.htm