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There's one question that needs to be addressed with any form of ion propulsion: what do you do with the opposite charged particles? In the diagram you've drawn, it's the positively-charged ozone ions that are being used for the propulsion. The electrons have to have somewhere to go too, otherwise your ionized gas will be electrically neutral and not repel ...

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Positronium is an exotic species composed of positron and electron. Depending on the allignment of the spins of postron and electron, the total spin of the positron can be zero or 1 (for the ground state for which l=0) and are designated as: ^1S (para-positronium) and ^3S (orto-positronium)

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There is a similar concept used by ballistic missiles called a Drag Reducing Aerospike It is a flat disc deployed forward of the nose that... The aerospike creates a detached shock ahead of the body. Between the shock and the forebody a zone of recirculating flow occurs which acts like a more streamlined forebody profile, reducing the drag. ...

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Watch a video of a rocket launch, say the space shuttle. Within a minute of the flight the launch director might make a statement about maximum dynamic pressure. The launch vehicle is producing a supersonic shock wave and the interaction of the atmosphere is at its peak. Within another $30$ seconds to a minute the dynamic pressure with the atmosphere is ...

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When you're considering hydrodynamic forces there are always two things to consider. One is the viscosity of the fluid, i.e. how much energy it takes to make it flow, and the other is the inertia of the object, i.e. how much energy it takes to make it move out of your way. At high velocities the drag is dominated by the inertial forces. Air weighs more than ...

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