Bussard ion drive?

[Zatnikitelman]

I don't expect to be a multi-gazillionaire any time soon so I guess there's no reason to hold onto this idea. Would a low earth orbiting satellite using an ion sustainer engine be able to refuel itself from the upper atmosphere similar to how a Bussard ramjet would work? I was inspired after seeing how the GOCE mission had to end its life because its ion sustainer engine had run out of fuel and it was pretty deep in the atmosphere due to the nature of its mission. Could a magnetic field in front of the satellite have scooped up the upper atmospheric gasses and either stored, or directly used them in an ion drive? What about the ISS? Could a collector be coupled with an ion or VASIMR drive to provide essentially limitless fuel even up at its orbit? What about the trace gasses in higher orbits? Are they enough to provide enough fuel at the lower speeds vs a true Bussard design?

 

[fsci123]

From what i remember, free oxygen is dominant at those altitudes and there may be problems trying to use it as propellant. Ionized oxygen has a tendency to bind to other materials.