The phrase “lightspeed ahead” will need to stay just that for now. While scientists continue to study ways to create faster, more efficient space travel within our solar system and beyond, a recent project to test NASA’s EmDrive determined that this thruster technology remains on the cusp of being a viable solution.
The EmDrive, an experimental space engine concept, is a hollow cone constructed from copper or other material that is placed in a frame. In theory, as natural microwaves bounce around inside the cone, they create a thrust to propel a rocket without the need to carry fuel. There just happens to be one major flaw with this idea: it defies current laws of physics.
A team of Technische Universität Dresden physicists in Germany decided to conduct its own test of the EmDrive, the SpaceDrive Project. The researchers presented their independent findings at the 2018 Aeronautics and Astronautics Association of France’s Space Propulsion conference. Their results showed that outside factors contributed greatly to the engine’s thrust.
Led by Martin Tajmar, the TU Dresden team built a replica of the EmDrive, or one that was as close as they could get based on leaked information. They then put their engine into a vacuum chamber and bombarded it with microwaves. They discovered that although the EmDrive experienced thrust, it was unlikely that it was produced by the engine since there was thrust regardless of the engine’s direction. This suggests that the Earth’s magnetism could be the point of the thrust’s origination. The report’s conclusion stated:
“First measurement campaigns were carried out with both thruster models reaching thrust/thrust-to-power levels comparable to claimed values. However, we found that, e.g., magnetic interaction from twisted-pair cables and amplifiers with the Earth’s magnetic field can be a significant error source for the EmDrive. We continue to improve our measurement setup and thruster developments in order to finally assess if any of these concepts is viable and if it can be scaled up.”
This suggests that previous tests that recorded a thrust may have been just a glitch. But, if other testing was accurate, than it could indicate that the laws of physics were defied in those small amounts of thrust.
In addition to testing the EmDrive, the team completed research on the Mach Effect Thruster, another improbable concept based on the idea that fluctuations generated in a piezo-crystal stack will create non-zero time-averaged thrust.
Using their vacuum chamber once again, the TU Dresden team noted more promising results, but not enough to prove it a valid idea. Although the thrust produced was 100 times more than was predicted, it stopped when the thrusters were off and did not work when the engine was put into reverse. The testing also suggested that as with the EmDrive, outside factors likely generated the thrust.
While these concepts still seem improbable as space travel solutions, the German team recommends further testing to truly verify or disregard their potential capabilities.