In the classic Star Trek episode titled, “The Doomsday Machine,” Capt. James Kirk and the crew of the starship Enterprise did battle with a monstrous, self-sustaining spacecraft that refueled itself by chopping up planets and anything else in its way.
A new scientific paper proposed the deployment of a much smaller spacecraft that would refuel itself by consuming debris in Earth orbit. The paper was written by Lei Lan, Jingyang Li and Hexi Baoyin of Tsinghua University in Beijing.
Abstract: We present a design concept for a space engine that can continuously remove the orbit debris by using the debris as a propellant. Space robotic cleaner is adopted to capture the targeting debris and to transfer them into the engine. Debris with larger size is first disintegrated into small pieces by using a mechanical method. The planetary ball mill is then adopted to grind the pieces into micrometer or smaller powder.
The energy needed in this process is get from the nuclear and solar power. By the effect of gamma-ray photoelectric or the behavior of tangently rub of tungsten needles, the debris powered is charged. This behavior can be used to speed up the movement of powder in a tandem electrostatic particle accelerator. By ejecting the high-temperature and high-pressure charged powered from the nozzle of the engine, the continuously thrust is obtained. This thrust can be used to perform orbital maneuver and debris rendezvous for the spacecraft and robotic cleaner. The ejected charged particle will be blown away from the circumterrestrial orbit by the solar wind. By digesting the space debris, we obtain not only the previous thrust but also the clean space. In the near future, start trek will not just a dream, human exploration will extend to deep universe. The analysis shown, the magnitude of the specific impulse for debris engine is determined by the accelerating electrostatic potential and the charge-to-mass ratio of the powder.
It’s an interesting idea. But, it reminds me of that old saying about the road to hell being paved with good intentions.