  Consuming long-range interplanetary medium with fuel for driving plasma
thrust is vital. Methods of capturing the space environment depending on its
density and the ship velocity are indispensable issues to extract the space
environment as a propellant. This matter of neutral fluxes would use solar
radiation to create ionization in a plasma thruster. Extracting propellant at
certain ranges look extremely promising where a low thrust device operates
continuously to deliver a celestial target close at the speed of light.
However, at longer distances, the density of space rapidly diminishes and it
may be impossible to maintain at a plasma thruster continuous operation mode
but instead might be workable with a pulsed engine. Nonetheless, at still
longer-range interstellar missions, the insufficient propellant will require
examining other alternatives than a plasma thruster for other candidate
propulsion system, possibly either propellantless or a propulsor is driven by
electric and/or magnetic fields to satisfy these mission objectives.
