NASA: New "impossible" engine works, could change space travel forever

[kahlzun]

In conventional terms, what this is, is the classic cartoon image of a boat with no wind. The solution? Pull out an electric fan, point it at the sail, and watch it go. Of course, in that case, newton's laws kick in, and any wind the fan is blowing, cancels out what hits the sail, and the boat goes nowhere.

Actually, the mythbusters tested that one, and the air being pushed out the sides of the sail actually did produce a net forward thrust. It was a good episode.

[Ralathon]

This is a typical case of the media hyping about things they do not understand.

NASA tested that engine, and an engine that was intentionally disabled so it shouldn't produce thrust. Both produced thrust.

This means there is probably some leak in the setup that allows radiation to escape the system, or there is some electronic interaction or whatever. It does not mean something revolutionary is happening here and people should stop getting exited about it.

[victory143]

I don't want sci-fi just yet

[N_las]

The laser itself won't produce thrust at all (if it did, we'd be using lasers instead of ion drives). The concept should work.

Thats BS. In exactly the same way the photons transfer momentum to the sail, they transfer momentum to the laser as they are emitted. The reason we use ion drives instead of simply using a laser shining out the back is apparent if you do the math: It would produce so little thrust for so much energy that even the worst imaginable ion engine would be unbeatable in comparison.

[Simon Ross]

Like many others on this post, my immediate reaction is HOAX !

However...

I am increasingly aware that our understanding of the forces that drive the universe are still woefully limited. Even in the last decade or so we have had to accept the theory of dark energy/matter simply to explain the huge gap between the theoretical mass and the actual mass of the universe in which we live.

So how would we view a device that tapped into dark energy/matter that could produce a net surplus of energy/useful work.

Pretty much the same way we currently view EM I would suspect.

Yet the device would not actually break any conservation laws, it would simply use an energy source that we don't currently understand and cannot directly detect.

Simon

[RuBisCO]

On to a cube sat to see if it actually works.

[Aghanim]

Validation method: As this is an RF cavity reactionless drive, instead of Woodward effect / QVP thruster, make the endplate removable. Test the engine with endplate and without endplate, put the endplate on top of the engine so the mass stays constant. If the thrust is similar, then they have reinvented photon drive, and there is nothing interesting going on. If the thrust is higher than the engine without endplate, then something really weird is going on.

[lajoswinkler]

Is there a valid reason why this thread isn't merged with this one?

http://forum.kerbalspaceprogram.com/threads/79291-EmDrive

[Dodgey]

On to a cube sat to see if it actually works.

Agreed, we don't always need to know why it works to know that it does work.

[Bacterius]

Why can't they just strap the device to a cubesat or other small satellite and see if it still produces thrust once in space? It doesn't cost that much to any company or agency, and it seems to me it would be an economical way to cast aside all doubts rather than testing with uncertainty on the ground. Or would it need to be tested in a higher orbit than LEO due to the atmospheric drag screwing up the observations, making the operation more expensive?

[Guest]

They're planning to. Negotiations with the ISS guys are ongoing, and it's possible it might be sent up there for evaluation in vacuum and zero-G.

[CaptainArchmage]

The designer for EM drive claimed the device operated on principles of relativity. NASA claims the effects were quantum in nature. There’s a world of difference between the two, and in fact quantum mechanics and relativity are viewed to be incompatible with one another. However, they are both considered valid. In quantum mechanics, you have virtual particle pairs (particle, antiparticle) which come into existence and annihilate one another. Those do have mass-energy (which is pervasive, throughout the universe).

Usually, when there is a hoax or mistake, there is one test article, produced by the original designer, or an anomaly that happens on a single test article. In this case, we have test articles produced by other scientists, and it appears there have been multiple built. I don’t think we can be skeptical here, we just need to run more tests.

On to a cube sat to see if it actually works.

As I have suggested.

Agreed, we don't always need to know why it works to know that it does work.

Which is why it needs to be tested. NASA attributes the function to quantum mechanics, if it is we may be able to better understanding the phenomenon. From an engineering perspective, however, the main matter will be to quantify the thrust produced by the thruster compared to the energy (and frequency) input.

Edited August 2, 2014 by CaptainArchmage

[Clockwork_werewolf]

As far as I understand it the drive has one very important point to understand. Firstly stationary energy loss is due to heat, in a perfect conductor the drive could produce force with no loss of energy. It could NOT produce thrust with no energy loss. The photons inside the chamber produce an unequal force due to quantum effects but as soon as the device accelerate then the force is negated. As such the device would have a very low acceleration but a very high force. Think of it this way, right now gravity is applying a large force to you but no energy is used or loss unless you more up or down. With a perfect conductor this would make a great hover device but not that good a thruster. It would however still be a fuel less thruster, so might be worth consideration.

[vger]

This means there is probably some leak in the setup that allows radiation to escape the system, or there is some electronic interaction or whatever. It does not mean something revolutionary is happening here and people should stop getting exited about it.

In the meantime, people who normally don't, are thinking about space, and NASA is getting some extra publicity. Quit complaining.

[CaptainArchmage]

On to a cube sat to see if it actually works.

In the meantime, people who normally don't, are thinking about space, and NASA is getting some extra publicity. Quit complaining.

This, exactly. NASA’s testing shows resulted, we need more testing. This might even be a “test your own†possibility.

It isn’t an energy-less thruster, it is just propellant-less in that no propellant is carried on board. It still requires energy to run. For a start it would simplify satellite design.

[RuBisCO]

As I have suggested.

I think I one-up you on that: http://forum.kerbalspaceprogram.com/threads/86010-KSP-Community-CubeSat?p=1270596#post1270596

Anyways if this works and can only produce thrust ratios (under earth gravity) below 1:1 it will still make for awesome propulsion in space, depending on the power source there could be no limits to where we could go and speed attained, we would still need to land on worlds using conventional reaction engines though. If this can produce thrust greater then 1:1 though: screw rockets, screw planes, screw cars, say hello to the fly car that can literally fly you to the moon and beyond (assuming the power source is just a radical).

Edited August 2, 2014 by RuBisCO

[Sky_walker]

Propellant-less drives are nothing new - solar sails, electrodynamic tether, etc. - drive that violates conservation of momentum on the other hand - is something... unexpected, to put it gently.

Besides - whoever is still excited about that - should read this post before building more pointless hype: http://forum.kerbalspaceprogram.com/threads/79291-EmDrive?p=1325513&viewfull=1#post1325513

[CaptainArchmage]

I think I one-up you on that: http://forum.kerbalspaceprogram.com/threads/86010-KSP-Community-CubeSat?p=1270596#post1270596

CaptainArchmage <- NINJA'D

Again, the principle using quantum mechanics isn’t reactionless - it pushes on virtual particle pairs (antiparticle-particle) that appear and annihilate. This is an engineering exercise.

Edited August 2, 2014 by CaptainArchmage

[RocketscientistV]

The Chinese got here before NASA and they both have positive results so I hold this in high hopes.

[Skyler4856]

So, a Casimir Vacuum thruster?

[jfull]

That would be AMAZING if it really does work, but I have some doubts.

Have they checked that this thing is ABSOLUTELY 100% propellantless? At this point, I have to wonder if this settup isn't somehow flinging metal atoms from the resonance chamber walls off into space to produce thrust.

They should leave it running for an long time and see if the engine loses any mass.

[RuBisCO]

I'm sure we are all skeptical, that why putting it on a cubesat and proving it in flight is the next phase.

[Ralathon]

I'm sure we are all skeptical, that why putting it on a cubesat and proving it in flight is the next phase.

"I'm sure we're all skeptical of the magic powder that supposedly cures all diseases. That's why injecting it into your bloodstream and proving it in a living human is the next phase"

Seriously, putting things in orbit over such sketchy 'evidence' is really stupid. It'd waste everyone's time and money, do some proper ground tests first instead of the sketchy and inconclusive research that we have.

[KerikBalm]

Not tested in a vacuum, wtf? they put it in a vacuum chamber, but left it at ambient pressure? wtf

then there's the possibilty of magnetic field interactions...

Better tests are needed before spending ~10,000 m/s of dV to get it into orbit

[RuBisCO]

"I'm sure we're all skeptical of the magic powder that supposedly cures all diseases. That's why injecting it into your bloodstream and proving it in a living human is the next phase"

Seriously, putting things in orbit over such sketchy 'evidence' is really stupid. It'd waste everyone's time and money, do some proper ground tests first instead of the sketchy and inconclusive research that we have.

Not for a cubesat, heck they orbited a cellphone, why? because they can.

So I don't see a reason why they can't launch an improbable propulsion system on a cubesat.

Edited August 3, 2014 by RuBisCO