NASA’s Eagleworks laboratories has recently released the results of their latest, upgraded experiments designed to evaluate a controversial propulsion device, one that does not use physical propellant to produce thrust, as traditional rockets use. Their verdict: the EmDrive appears to work. As this drive would provide continuous acceleration, it would make space travel much faster. A trip to Mars, for example, could be cut from months to just a few weeks. The drives being tested now provide very little thrust, but much more powerful engines can be built.



The EmDrive, short for Electromagnetic Drive, was first proposed and built by British engineer Roger Shawyer in 2001. While it produced only a minor amount of thrust, the development of such an electrically-powered propulsion source would revolutionize space travel: currently, travel to other planets is severely limited by the ability of the vehicle to accelerate, of which requires the expenditure of bulky fuel that would otherwise have to be transported along with the vehicle.



Since the mass of the fuel that would be required for constant acceleration would be prohibitively heavy for current space probes to carry, they instead gain nearly all of their speed during their launch into space. After that, aside from gravity-assists picked up from planets that they may travel near, these spacecraft rely entirely on the momentum gained during launch for the duration of their journeys. An electrically-powered craft, on the other hand, would not need to carry the extra mass, and thus could accelerate for the entirety of the trip, being powered by solar panels or radioisotope thermoelectric generators.



When it was introduced, the EmDrive was met with near universal scorn, due to what many perceived as a violation of Newton’s Third Law of Motion. The device, instead of accelerating some sort of mass such as rocket fuel to produce it’s thrust, focuses microwaves through a cone-shaped tube that is closed on it’s ends, and reflects them back through the tube to produce motion.



Despite this criticism, the device has been duplicated in a number of experiments since it’s introduction, with many research teams reporting success. Researchers at China’s Northwestern Polytechnical University have even gone so far as to hypothesize that the thrust is produced from an interaction with what they refer to as the "quantum vacuum virtual plasma", however this idea remains unexplored.



Critics of the device have been quick to point out the myriad variables that could be producing the apparent thrust, however NASA’s latest experiments were designed to address and eliminate as many of these variables as possible; chief among them is a possible Lorenz force interaction, where electrons that encounter magnetic fields produce a minor propulsive force. However, even after eliminating these environmental conditions, Eagleworks labs found that they were still measuring over 100 uN (micro Newtons) of force being generated by the device. While this is not a large amount of thrust, it is promising that this might provide a revolution in propulsion technology — and possibly a revolution in our culture’s current model of physics.