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NASA's Impossible Propulsion EmDrive Is Heading to Space (popularmechanics.com)
An anonymous reader writes:The EmDrive, a hypothetical miracle propulsion system for outer space, has been sparking heated arguments for years. Now, Guido Fetta plans to settle the argument about reactionless space drives for once and for all by sending one into space to prove that it really generates thrust without exhaust. Even if mainstream scientists say this is impossible. Fetta is CEO of Cannae Inc, and inventor of the Cannae Drive. His creation is related to the EmDrive first demonstrated by British engineer Roger Shawyer in 2003. Both are closed systems filled with microwaves with no exhaust, yet which the inventors claim do produce thrust. There is no accepted theory of how this might work. Shawyer claims that relativistic effects produce different radiation pressures at the two ends of the drive, leading to a net force. Fetta pursues a similar idea involving Lorentz (electromagnetic) forces. NASA researchers have suggested that the drive is actually pushing against "quantum vacuum virtual plasma" of particles that shift in and out of existence. Most physicists believe these far-out systems cannot work and that their potential benefits, such as getting to Mars in ten weeks, are illusory. After all, the law of conservation of momentum says that a rocket cannot accelerate forward without some form of exhaust ejected backwards. Yet the drumbeat goes on. Just last month, Jose Rodal claimed on the NASA Spaceflight forum that a NASA paper, "Measurement of Impulsive Thrust from a Closed Radio Frequency Cavity in Vacuum" has finally been peer-reviewed and accepted for publication by the American Institute of Aeronautics and Astronautics, but this cannot be confirmed yet.
Does it count as an argument if I point out that the titular claim is full of hot air?
The guy behind the idea has (at least according to himself) formed a company with the stated goal of getting this thing into space. There's no scheduled launch in place yet, nor any specific plan. No mention of funding either, although a different guy is apparently launching a Kickstarter to get his own version into space. Don't worry, if it never goes I'm sure he'll spend the money wisely.
Right now it's all hand-waving, which means the concept is at pretty much the same place it's always been.
#DeleteChrome
The paper from Dresden is available in English: https://tu-dresden.de/ing/masc... Of the chinese paper, I only know English reports of the abstract, such as from https://www.reddit.com/r/EmDri...
NASA's Impossible Propulsion EmDrive Is Heading to Space
It's not NASA's.
systemd is Roko's Basilisk.
3) a test in space is likely to be a short mission with release and capture over a few meters of flight, if that. This is not sufficient to rule out outgassing.
I have discovered a little-known practice called "reading the article" that can help clarify what is proposed:
Fetta intends the satellite to stay on station for at least six months, rather than the six weeks that would be typical for a satellite this size at a altitude of 150 miles. The longer it stays in orbit, the more the satellite will show that it must be producing thrust without propellant.
I don't care if it's 90,000 hectares. That lake was not my doing.
a bowl of petunias and a very surprised looking whale....
i wonder if it will be friends with me? ...
- Douglass Adams RIP