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A larger version of the smaller one. Runs on H2, He, O2, H20, C02, CH4. On H2 it consumes 33.3MW of power to produce 422N at 143km/s...

An MPD with both very high thrust and exhaust velocity but downright absurd power requirements. Personally, I used a Black Box to power it--it's really more a proof of concept than anything else. Stats: -Propellant: Water -Exhaust Velocity: 1.11 Mm/s -Thru...

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A tiny, lightbulb-sized ball of potassium plastered together to turn your tiny rockets around in an "affordable" manner. These small lads barely cost one half-credit per unit (476mc) and probably won't implode or melt from having 796 KiloWatts thrust throu...

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So Apparently with Mercury, Carbyne, and a measurable fraction of the energy produced by the sun per second you can break the speed of light. I don't think you can make anything more efficient, but I welcome anyone to try. Good luck trying to power this th...