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A comment on Breaks Observed in Rover Wheel Treads. Parent comment

Re:Breaks Observed in Rover Wheel Treads by jerf on Wednesday March 22, 2017 @10:59AM (#13931444)
Minmus surface gravity is 0.491 m/s^2; current ion drives thrust with a couple hundred millinewtons, so I don't think a drive could even support itself against that level of gravity let alone with power and a ship attached.

However, we currently design our ion drives for power-to-thrust efficiency and long-term effectiveness. I'm not sure what we could get if we designed them for maximal thrust. Especially since in real life, right now the answer to "Do you want a 'maximal thrust' ion drive?" is pretty much "Well, have you considered using... not an ion drive?", so I'm not sure I've ever seen a treatment of that question based on current tech.

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Re:Breaks Observed in Rover Wheel Treads by creshal on Wednesday March 22, 2017 @11:06AM (#13931498)
> I'm not sure what we could get if we designed them for maximal thrust.

Probably something with a worse specific impulse than a chemical engine.

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Re:Breaks Observed in Rover Wheel Treads by Symmetry on Wednesday March 22, 2017 @01:44PM (#13933047)
The problem is less our ability to make the drives themselves have a high TWR (thrust to weight ratio) so much as that the power generation necessarily required to run them is very heavy. See here:

http://hopefullyintersting.blogspot.com/2015/03/rockets-elec...

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Re:Breaks Observed in Rover Wheel Treads by skykooler on Wednesday March 22, 2017 @02:50PM (#13933612)
The VASIMR engine is sort of that - an ion engine designed to be able to increase thrust when needed.
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