Ion Engines Interactive - Design Your Own Ion Engine


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Design Your Own Ion Engine

Ions shooting out the back of the engine, driven by the charge differential in these plates, produce thrust for the rocket.

Your Mission

Maximize the total impulse provided by the ion engine as represented by the rocket at the top of the display.

  • When you press LAUNCH, electrons are emitted by the blue electrode.


  • Adjust the Plate Location slider to change the plate separation distance.
  • Adjust the Plate Charge slider to change the charge strength.
  • Click the Launch button; blue ions get accelerated.
  • Click the Stop button to reset.


  • Notice that the ions are accelerated between the plates. Adjust separation between the plates so control how many ions hit the plates.
  • If an ion or electron hits a plate or the walls of the Ion Engine, it will emit a brief white flash and then disappear.
  • Decreasing the charge means the plates won't accelerate the charges with as much force.
  • Increasing the charge on the plates means that more energy goes into each ion. Warning: limited energy supply!

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