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EmDrive  (Source: emdrive.com)
It's a a propellantless microwave thruster that defies Newton's laws of motion

Chinese scientists have taken on a heavily criticized space drive idea that could one day launch satellites, deep space probes and even flying cars.

The research team hails from Northwestern Polytechnic University in Xi'an, and was led by Yang Juan. What they developed was a propellantless microwave thruster called EmDrive, which is a controversial idea because it goes against Newton's laws of motion -- and many have claimed to create a "propellantless" thruster before and failed.

Newton's laws of motion are all based on the idea that firing propellant out of the back at a high speed will push a craft forward. While solar cells offer infinite power, thrust is limited by propellant. Many have tried to get around this, but several scams have made this particular field a joke in the scientific world.

While space drives tend to rely on Newton's laws of motion, the EmDrive is a closed, conical container that has a net thrust toward the wide end when filled with resonating microwaves. This goes against Newton, who said that no closed system could have a net thrust. However, EmDrive works because the microwaves have a group velocity (the speed of a collection of electromagnetic waves) that is greater in one direction than the other -- which is where Albert Einstein's theory of relativity comes in.

British engineer Robert Shaywer, who began looking at the concept of a propellantless thruster when he opened his own company called Satellite Propulsion Research in 2001, is the original creator of the EmDrive. He made demonstration thrusters to prove it could be done, and even made sure the test results were accurate (meaning, the results weren't affected by friction, ionization, air currents, electromagnetic effects or interference). The first, made in 2003, had a thrust of 16 mN. This was enough to show it could be done.

However, he received a ton of criticism for his idea and was ridiculed in his own country. But the Chinese team at Northwestern Polytechnic University believed in his research and took the project head on to author the latest study, "Net Thrust Measurement of Propellantless Microwave Thruster."

The Northwestern Polytechnic University team was able to create the EmDrive with 720 mN of thrust with a couple of kilowatts of power.

So what purpose does EmDrive have? It could halve launch costs of satellites because as much as half the launch weight of these objects are attributed to propellant.

Shawyer is even working on a superconducting thruster that could be ready as soon as 2016. It would boost the Q value of the cavity, which determines the amount of thrust produced. He said it could be boosted by a factor of several thousand, possibly equating to a tonne of thrust per kilowatt of power.

Source: Wired



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By omgwtf8888 on 2/14/2013 11:54:06 AM , Rating: 2
I agree that education should not be limited to academics and college. We are failing at introducing children to meaningful education in the trades and crafts. At least in my experience, in NJ, if you went to the vocational high school you were pretty much deemed a loser/junky. Shop courses have been virtually eliminated. Without introduction to these career choices many kids may never find a career that they could have been passionate about. In your comment you reference that failing students in Asian schools are left to manual labor, i refer to them as cast out. The manual labor/low education/skills jobs are rapidly drying up in the United States. Many of these jobs are filled by illegal aliens. Of course the standard blurb that we are fed is that the illegals are doing jobs Americans do not want. What the illegals are doing is jobs that Americans do not want at that low of a wage. The large supply of illegal (sub minimum wage) labor drives down the salary and benefits that would otherwise have to be paid for these jobs. Unfortunately it is going to get worse. As we move to autonomous vehicles, the last high paying low skill jobs: truck driver, taxi/limo driver are going away. So really with the exception of adding more trade/craft training we are not going to have any manual labor jobs. So the U.S is ahead of the curve in recognizing that the entire populace has to be educated or the subsequent have/have not divide will be so great that conflict is inevitable.


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