NASA Successfully Tests Ion Engine

Robert Clark wrote:
Would this provide a low energy means of creating the plasma
required for ion engines? One means of creating the required plasma
is by irradiating the propellent gas with intense laser or x-ray
beams to strip off the electrons of the atoms of the gas, producing
an ionized plasma. However, these are both high-frequency forms
of EM radiation and therefore require high energy to produce.
Microwaves being longer wavelengths require less energy to produce.

Microwaves being longer wavelengths have less energy *per* *photon*.
The energy it takes to ionize a gas is the same regardless of how you
do it. If you use microwaves, you nead more photons, but the same
number of watts.
--
Keith F. Lynch - - http://keithlynch.net/
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