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A Chinese newspaper and other sources are reporting that China is already testing an EmDrive thruster in space, aboard the Tiangong-2 space station:
[Researchers] in China have announced that they've already been testing the controversial drive in low-Earth orbit, and they're looking into using the EM Drive to power their satellites as soon as possible.
Big disclaimer here - all we have to go on right now is a press conference announcement [archive.is] and an article from a government-sponsored Chinese newspaper (and the country doesn't have the best track record when it comes to trustworthy research).
[...] But what the China Academy of Space Technology (CAST) team is saying also corresponds with information provided to IB Times from an anonymous source. According to their informant, China already has an EM Drive on board its version of the International Space Station, the space laboratory Tiangong-2.
[Continues...]
It had been recently suggested that the U.S. is testing an EmDrive aboard the X-37B spaceplane:
In November 2016 the International Business Times claimed the U.S. government was testing a version of the EmDrive on the Boeing X-37B and that the Chinese government has made plans to incorporate the EmDrive on its orbital space laboratory Tiangong-2. In 2009 an EmDrive technology transfer contract with Boeing was undertaken via a State Department TAA and a UK export licence, approved by the UK MOD. The appropriate US government agencies including DARPA, USAF and NSSO were aware of the contract. However, prior to flight, the propulsion experiment aboard the X-37B was officially announced as a test of a Hall-effect thruster built by Aerojet Rocketdyne.
Some are already envisioning probes that could reach far beyond the Kuiper belt (thousands of astronomical units) in around a decade. This would allow the exploration of trans-Neptunian objects such as Sedna (around 86 AU from the Sun, with an estimated aphelion of 936 AU) and the hypothetical Planet Nine (estimated to be between 200 and 1,200 AU away).
We must not allow an EmDrive gap.
Also at redOrbit, and Chinatopix, which notes that previous Chinese EmDrive tests have resulted in false positives and that the EmDrive was not publicly listed among the items brought aboard the Tiangong-2 in October.
Previously: EmDrive Peer-Reviewed Paper Coming in December; Theseus Planning a Cannae Thruster Cubesat
It's Official: NASA's Peer-Reviewed EmDrive Paper Has Finally Been Published
(Score: 2, Interesting) by anubi on Monday December 26 2016, @06:30AM
A little offtopic - but another take on propulsion which does not involve ejecting mass in order to get a force ( F=MA ).
I got into a discussion a few months ago with a friend over whether the Cook Inertial Propulsion system [rexresearch.com]
would work.
He believes in it. I do not.
He says he can feel the centrifugal force when he slings something. I say he feels an equal and opposite ( force*time ) accelerating and decelerating the mass, and the loop integral must always be zero. Play with a paddle ball all you want, but until the rubber band breaks, you are not going to get any net delta velocity.
I was hoping the following analogy would be convincing, but failed. Consider the path of the mass being handled that provides the inertia. At some point in time, the mass will be somewhere along that path. Now replace the pathway with a pipe of the same curvature - and pump water ( a continuous mass ) along the circuit. Does the whole shebang do anything but make noise and get hot?
As far as I am concerned, what I have seen looks similar in function to those old motor-driven bed vibrators - and all it can possibly do is rock, rattle, and roll. It won't go until it slings itself apart.
Now, this way of doing it with microwaves within a resonant chamber puzzles me. None of the physics I know support it. One thing I do not know is if there is a magnetic field that permeates space in the same manner we have a localized magnetic field covering this entire planet. I believe if there is such a thing, magnetic propulsion will work - as the spaceship becomes the rotor in a galactic sized stator. However there seem to be a lot of illusions that will play out like a Bedini motor - which is yet another thing I have had heated discussions over, as I fail to see where that particular setup to get work out without putting work in can possibly function.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 3, Informative) by mhajicek on Monday December 26 2016, @08:00AM
Inertial swimming is a thing, but only works in a gravity well:
http://physics.stackexchange.com/questions/46180/can-a-deformable-object-swim-in-curved-space-time [stackexchange.com]
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 2) by fritsd on Monday December 26 2016, @10:55AM
I am not a physicist, but I think you're talking about the old-fashioned Æther theory [wikipedia.org].
I first read about it as a boy in the fantastic "Suske en Wiske" cartoon "De Wolkeneters [wikipedia.org]" (# 53), where professor Barabas makes a rocket that flies according to this principle. I've always loved Science Fiction (most of the other hundreds Suske and Wiskes are not sci-fi, but a few are really good! Dunno if they've all been translated into English. Nurture your inner child, read a Suske en Wiske [wikipedia.org] today! Here endeth the slashvertisement.).
What I do know about magnetic fields is that they are always dipoles [wikipedia.org], and that means that the field strength as a function of distance doesn't go as one over r squared, but instead as one over r^3 [wikipedia.org].
That is why you need a lot of strength to pull two mini candy bar sized Neodymium magnets apart, but they won't have a large effect at distance.
I think you might find this page interesting: Michelson-Morley experiment [wikipedia.org].
(Score: 0) by Anonymous Coward on Monday December 26 2016, @11:26AM
there are two options.
either what they call "EM-drive" is something completely different from what they think, in the sense of new physics, or it's pure shit.
if nothing comes of it in another couple of years, it means it's shit.
(Score: 2) by takyon on Monday December 26 2016, @01:06PM
EmDrive must be tickling something inside of you, because you're willing to give it two more years!
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Monday December 26 2016, @06:45PM
there is now a peer reviewed paper where they detail an experiment where a force is measured, even though i don't expect a force to be there.
i'm pretty sure others will try to replicate this within 2 years, and apparently it's not hard to scale it up, so they should also do that.
If the results are real, then it is an unexplained phenomenon.
I don't have the time to figure out if the people claiming these results are trustworthy or not, and i don't know enough about quantum field theory to try to figure out whether this may be real.
i am willing to bet my PhD that, if the effect is real, there is definitely more than Maxwell's equations behind it.
hence my waiting for confirmation from the mainstream, or at least some hovering black box that is being sold by these people, with them claiming trade secrets, hence no explanation.
(Score: 1) by anubi on Tuesday December 27 2016, @08:08AM
This is the same logic conundrum I run into trying to prove or disprove Rossi's E-Cat.
Personally, I think he's running a very profitable theater for men of the suit and tie to throw money into. The stuff I have seen so far ( The videos he sent to Steven Krivet of New Energy Times ) to me demonstrated nothing more than a fantastically expensive tea kettle which probably made bad tea.
However, I remain unconvinced that cold fusion is impossible. I do not think he is on the right track, but neither do I have a PhD, nor do I think monied people give much of a damn about any insight I may have either.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 0) by Anonymous Coward on Monday December 26 2016, @02:18PM
> Now replace the pathway with a pipe of the same curvature - and pump water ( a continuous mass ) along the circuit. Does the whole shebang do anything but make noise and get hot?
From watching coiled hoses, the loop will also try to straighten out (uncoil).
(Score: 1) by anubi on Tuesday December 27 2016, @08:29AM
That it will ( uncoil ). Noted especially in something like a fire hose.
Now imagine you are in a boat, along with, say, 25 feet of hose, a water pump, and a power source. The pump is connected to pump water through the hose back to the pump inlet. You cannot cut the hose, but you are allowed to form the loop in any geometry you want. What you now have is a mass of water moving in a loop of any geometry of your choosing. You may change the diameter of the hose ( velocity of the mass ) or the geometry of the hose on the fly if you want to. What you cannot have is a leak in or out of the hose. That is you have to use the same water over and over again. You cannot intake or eject any. Can you propel the boat in this manner?
( Yeh, I know, the easy way would be to cut the hose, place the suction end at the bow, the outlet end at the stern - and you will go. That concept is already in use to propel boats through swampland. )
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 0) by Anonymous Coward on Monday December 26 2016, @04:20PM
Bogus, bogus, bogus.
I don't fully understand his proposed device from reading that page, but the justification for how it works is bogus. He invokes a helicopter traveling at constant speed, and notes the difference in kinetic energy of the advancing and retreating blades, obviously without noting the dependence on reference frame.
If you can't be bothered to explain its operation either in terms of momentum (which is conveniently linear and well-behaved for this sort of problem), or to point out why you chose a weird and difficult to compute reference frame instead of the obvious and convenient one, that's a bit of a red flag. When you actively contrast two identical cases, differing only in choice of reference frame, and pretend they represent a difference in physics rather than a difference in perspective, you've gone full-on perpetual-motion nutter.
(Score: 3, Informative) by butthurt on Monday December 26 2016, @07:03PM
One thing I do not know is if there is a magnetic field that permeates space in the same manner we have a localized magnetic field covering this entire planet.
According to another commenter, Tiangong-2 orbits at an altitude of 238 miles (384 km).
/breakingnews/comments.pl?sid=15530&cid=402278 [soylentnews.org]
I don't have data on it, but the Earth's magnetic field will be of similar strength there to what it is at the surface. Satellites sometimes include magnets that provide attitude control by interacting with Earth's magnetic field.
https://en.wikipedia.org/wiki/Magnetorquer [wikipedia.org]
http://staff.ee.sun.ac.za/whsteyn/Papers/Magsat.pdf [sun.ac.za]