The Tyranny of the Rocket Equation

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https://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html

Here the approximate cost in energy has been given in terms of velocity (kilometers per second, km/s), a common ploy engineers use to simplify the discussion. These numbers assume ideal conditions such as no losses for atmospheric drag or combustion but are close enough for the sake of this illustration.

 

 

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