NASA’s EM Drive, or EmDrive, has been tested again by Eagleworks, and this time, the second generation EM Drive produced even better results. Often wrongly referred to as “NASA’s warp drive,” the not-so-faster-than-light Cannae engine still manages to break Isaac Newton’s laws of physics, seemingly producing thrust out of nowhere. The best part is that it’s possible the EM Drive could cut down the time for a manned mission to Mars.
In a related report by the Inquisitr, NASA is planning to terraform Mars, and the Mars One crew has already talked about wanting Martian babies.
Building An EM Drive Spaceship For Mars Travel
NASA is excited about the potential for using the EmDrive in a working spacecraft. Specifically, a useful EM Drive for space travel would need a nuclear power plant of 1.0 MWe (Megawatts-electric) to 100 MWe. The technology necessary for building such a space-based nuclear power plant has been around since the 1980s, and the U.S. Navy already manufactures 220 MW reactors for ICBM nuclear missiles.
Harold White, the leader of the research group at Eagleworks, predicts that a crewed mission to Mars inside a 2 megawatt nuclear electric propulsion spacecraft could get to Mars within 70 days, assuming the NASA EM Drive can provide a thrust/power input of 0.4 Newton/kW. To put this achievement into perspective, the old Apollo equipment took three days to reach the moon.
Enter The Controversy
The concept of the NASA EM Drive has been met with great skepticism among the scientific community. Part of the reason that many reports have referred to a NASA warp drive is because of some earlier tests. When lasers were fired into the resonance chamber of the EmDrive, some of the beams were found to be traveling at speeds exceeding the speed of light. Thus, some thought NASA may have accidentally created a warp field, or warp bubble.
In response to the idea that they were creating a NASA warp drive engine, the space agency issued a statement.
“While conceptual research into novel propulsion methods by a team at NASA’s Johnson Space Center in Houston has created headlines, this is a small effort that has not yet shown any tangible results. NASA is not working on ‘warp drive’ technology.”
In reality, the EM Drive is more of a reactionless drive than a warp drive. It uses a higher-powered vacuum tube, called a magnetron, to direct microwaves at the short end of a truncated cone within a resonance chamber, but even this basic description is considered controversial, since it would seemingly violate Isaac Newton’s conservation of momentum. Since the EM Drive’s thrust does not work by any known force, some believe there is unaccounted phenomena creating the thrust, or that there is an error in the concept of the resonant chamber thruster.
The Physics Of An EM Drive
The Cannae drive is NASA’s version of the EM Drive concept, and they believe it “is potentially demonstrating an interaction with the quantum vacuum virtual plasma.” That explanation sounds awfully like Star Trek gobbledygook, but trying to explain virtual particles is way beyond the scope of this article.
In short, virtual particles are arising out of fluctuations in the quantum vacuum, which is the lowest possible energy point in a quantum state. These virtual particles are then ionized by the microwaves, and thus the EM Drive works similar to an ion drive, except without the need for ionized propellant.
Still, this explanation is unconvincing to some scientists, since it’s assumed that a quantum vacuum cannot be ionized. In order to generate thrust, and obey the conservation of momentum law, there needs to be something to “push” against, and a quantum vacuum supposedly does not provide this ability. A quantum vacuum is also not a plasma.
However, British scientist Roger Shawyer, inventor of the EM Drive, claims his device has no quibble with Sir Isaac Newton.
“To put it simply, electricity converts into microwaves within the cavity that push against the inside of the device, causing the thruster to accelerate in the opposite direction,” he said.
Engineers over at NASA’s Eagleworks Laboratories have been trying to work out whether or not the EM Drive’s thrust results are real for years. Earlier in 2015, NASA scientists ruled out one main source of an error by showing that the EmDrive engine works in a vacuum.
Shawyer’s theory has also been confirmed by other countries. Last year, Chinese scientists independently proved the EmDrive theory by constructing a similar engine which could generate 720 mN (milli-Newton) of thrust using 2.5kW of energy. In July of 2015, researchers in Germany submitted their own thrust measurements of another experimental EmDrive.
Recently, Paul March, one of the people working on NASA’s EmDrive, published an informal update on the NASA Spaceflight forum. One of the potential sources for thrust is the Lorentz force, which is when two interacting magnetic fields apply a combination of electric and magnetic force on a single point. The reason Lorentz force may be an issue is because the magnetic field generated by the Earth may be interacting with the EM Drive’s field, which would make the unaccountable thrust useless in deep space.
March said recent upgrades to the EM Drive may address such concerns.
“I will tell you that we first built and installed a 2nd generation, closed face magnetic damper that reduced the stray magnetic fields in the vacuum chamber by at least an order of magnitude and any Lorentz force interactions it could produce. I also changed up the torque pendulum’s grounding wire scheme and single point ground location to minimize ground loop current interactions with the remaining stray magnetic fields and unbalanced [DC] currents from the RF amplifier when it’s turned on… Finally we rebuilt the copper frustum test article.”
The NASA engineer’s explanation enters into more detail, but in short he says they reduced the Lorentz force interaction to less than one micro-Newton (uN), yet they are still seeing over 100uN of force/thrust generated with only 80 watts of power (keep in mind their input power for these experiment is much less compared to the Chinese experiment). To put the effect of the Lorentz force into perspective, it’s about the size of a mosquito applying its weight on a surface.
There was a secondary issue that March addresses in his long explanation. Another potential source of contamination causing the thrust may be thermal expansion, which only becomes a bigger problem in a vacuum, or outer space, due to insulation.
“These new plus and minus thrust signatures are still contaminated by thermally induced TP center of gravity (cg) zero-thrust baseline shifts brought on by the expansion of the copper frustum and aluminum RF amp and its heat sink when heated by the RF, even though these copper and aluminum cg shifts are now fighting each other… We are now working on a new integrated test article subsystem mounting arrangement with a new phase-change thermal management subsystem that should mitigate this thermally induced TP cg baseline shift problem once and for-all.”
The NASA team is currently working on an analysis tool for the thermal expansion issue, but so far the results are promising. In the end, March says the “anomalous thrust signals remain,” which is a cause for celebration.
[Image via Elvis Popovic]