Electric Universe Model.,

[papageno]

This nozzle opening is exactly missing from all the observations thusfar; pure speculation. Maybe Rosetta will be close enough to image such a nozzle, but be prepared to find a "bright spot" staring back at the camera, and no "nozzle" in sight.

The idea that a hole in a dark surface might appear as bright spot seems to be alien to you.

Btw, wouldn't the dust particles collide amongst themselves (and thus broaden the jet) when the "nozzle" analogy is true?

Extracting from the post you just quoted:

This is because the absence of a viscous interface at the jet boundary means there will be no hydrodynamic instabilities to break the jet apart, any instabilities have to be internal. But the jets are not dense, so internal instabilities will not be important. And since the jets are not dense, if they are not collisional, then multiple scattering of jet particles off of each other will not cause the jets to decollimate.

If you like analogies, think of shrapnel from an explosion.

[VanderL]

The idea that a hole in a dark surface might appear as bright spot seems to be alien to you.

Don't be ridiculous, you obviously haven't looked at images of the bright spots; if you had, you would have known that they are NOT a hole in the surface.

Extracting from the post you just quoted:

Quote:
Originally Posted by Tim Thompson
This is because the absence of a viscous interface at the jet boundary means there will be no hydrodynamic instabilities to break the jet apart, any instabilities have to be internal. But the jets are not dense, so internal instabilities will not be important. And since the jets are not dense, if they are not collisional, then multiple scattering of jet particles off of each other will not cause the jets to decollimate.

If you like analogies, think of shrapnel from an explosion.

How dense is not dense?

Cheers.

[VanderL]

Quote:
Originally Posted by VanderL
The ions and gas molecules you mention may fit the standard model, but only if the "parent volatiles" can be shown to exist and if these volatiles can be shown to get enough heat to generate jets. If they don't exist in large enough quantities (and the results show no indication of them) the ions/molecules and very fine grained dust can be explained by EDM.

Parent Volatiles in Comet 9P/Tempel 1: Before and After Impact; Michael J. Mumma, et al.; Science 310(5746): 270-274 (October 2005).
Abstract: We quantified eight parent volatiles (H2O, C2H6, HCN, CO, CH3OH, H2CO, C2H2, and CH4) in the Jupiter-family comet Tempel 1 using high-dispersion infrared spectroscopy in the wavelength range 2.8 to 5.0 micrometers. The abundance ratio for ethane was significantly higher after impact, whereas those for methanol and hydrogen cyanide were unchanged. The abundance ratios in the ejecta are similar to those for most Oort cloud comets, but methanol and acetylene are lower in Tempel 1 by a factor of about 2. These results suggest that the volatile ices in Tempel 1 and in most Oort cloud comets originated in a common region of the protoplanetary disk.

Quote:
Originally Posted by VanderL
No, it doesn't, you need to heat subsurface material efficiently through a dark "shell" and hope to get it jetting (never saw any references that actually show how this is achieved).

Here is a reference: Introduction to Comets; John Brandt & Robert Chapman, Cambridge University Press, 2004 (2nd ed). See chapter 7, "The Nucleus", and specifically section 7.3.2 (pages 249-258 in my paperback edition). There you will see a discussion of the thermal properites, sublimation rates, the basic thermodynamic stuff you are looking for. You will also find that "No, it doesn't" is a factually incorrect response. A factually correct response would have been something like, "yes, it does". We can, in fact, readily explain comet jets by virtue of heat tansferred from the outer layers. Why this should seem to you to be such a problem is beyond me. Even common sense should tell you this would work; with such dark outer layers as comets usually have, heat absorption is not much of an issue.

Thanks for the reference (is there an on-line reference for the details in the Brandt & Chapman book?), I'm trying to find out if the observed quantities are sufficient to explain the jets, especially since the Wild 2 data showed spikes and bursts that needed a new explanation (fragmentation) to get the data fit into a model. EDM would be able to break the molecules of the comet into it's constituents, which are then able to recombine (in the coma) in every other possible configuration (there's lots of ions in the coma).
The dark side jets are still a problem, because thermal inertia for comets is practically zero, as the data from Tempel 1 showed.

Something else that I noticed is that the fit to a model is always a very vague statement, like "well", "reasonably well" or something like that.

The jetting observed far from the Sun is still a big problem, there is simply no heat to get anything to outgas, let alone jet.

About the X-wind model: bipolar jets are indeed ubiquitous, but how would anything expelled by such a jet end up in the Kuiper belt (and then "melt" together with the presumed ices?)

Cheers.

[biknewb]

I am not astonished at your astonishment. Since you are unfamiliar with the relevant science, your astonishment is par for the course. In fact, a jet in a vacuum should remain collimated much better than a jet which is not in a vacuum, so the expected by science is exactly the opposite from the expected by you. This is because the absence of a viscous interface at the jet boundary means there will be no hydrodynamic instabilities to break the jet apart, any instabilities have to be internal. But the jets are not dense, so internal instabilities will not be important. And since the jets are not dense, if they are not collisional, then multiple scattering of jet particles off of each other will not cause the jets to decollimate.

These jets specifically may not have been modeled, I don't know. But comet jets are modeled in general, and their observed behavior is consistent with the model results. See, for instance, Modeling CN Jets of Comet Hyakutake (C/1996 B2), Modeling the Nucleus and Jets of Comet 81P/Wild 2 Based on the Stardust Encounter Data, Analysis of OH, CN, and C2 Gas Jets in Comet Hale-Bopp through Monte Carlo Modeling.

These are only examples, but they make the point. There is in fact a considerable research done on the comet jets, and the research indicates that the observed behavior of the comet jets is consistent with the expectations of the various standard models. This should not be surprising, because the standard models are based, after all, on fairly standard physics. In particular, whether or not the jet is narrow or broad, well or poorly collimated, or even broadly fan shaped, depends entirely on the morphology of the nozzle, which in this case is the hole in the comet that the jet will come from. And keep in mind that the morphology should not be expected to always be constant with time.

Finally, see also the book Introduction to Comets, John Brandt & Robert Chapman, Cambridge University Press, 2004 (2nd ed). See chapter 7, "The Nucleus", which details both observation & modeling of a comet nucleus, jets included.

Thanks. I have been looking for links like these.

[biknewb]

10 Megaohms is not particulary high as conductance.
My skin is at times better conducting than that, without sweating.

The point is how much.
Is such a conductance enough for EDM-like effects, as proposed by iantresman?

Haven't found specs on that yet.
Most earth based EDM is performed on metallic compounds.

[papageno]

Don't be ridiculous, you obviously haven't looked at images of the bright spots; if you had, you would have known that they are NOT a hole in the surface.

A hole in the relatively hard surface of a comet, through which material from the relatively soft inside can escape in the form of jet, is not inconsistent with the observations of the jets. Such a hole would work as a nozzle.
If the surface is dark, and the inside less dark, the hole would appear brighter than the surrounding.
This is, of course, speculation.

Now, do you have physical argument based on observation, that exclude the possibility that some of those bright spots you are so fond, are not nozzle-like openings?


From one of the references you quoted:

It is brighter than its surroundings and is seen in different images, ruling out the possibility that it is a phase effect or image artifact. In stereoimages, it has no height and appears to be an enhanced albedo spot on the surface, but it cannot be ruled out that the feature is not sunlight reflected off a short dust jet. There is an adjacent shadow-like dark spot that could be the shadow of an optically thick jet, but it appears to be the shadow of an adjacent small ridge. Several other bright spots are seen on the comet, some associated with irregular depressions. Whether these brightenings on an otherwise black surface are due to grain-size effects, condensed materials, or other processes is an intriguing question

(bolding mine)

How dense is not dense?

Not dense enough to break the jet.

By the way, you have not addressed this post:

So, where is the evidence that the surface of comets are conductive enough?
The space probes we sent out are made of metal: where is the EDM?

[...]

Do you remember that the Solar Wind is macroscopically neutral?
How do you build up a voltage between the comet's surface and the environment?

[VanderL]

A hole in the relatively hard surface of a comet, through which material from the relatively soft inside can escape in the form of jet, is not inconsistent with the observations of the jets. Such a hole would work as a nozzle.
If the surface is dark, and the inside less dark, the hole would appear brighter than the surrounding.
This is, of course, speculation.

Now, do you have physical argument based on observation, that exclude the possibility that some of those bright spots you are so fond, are not nozzle-like openings?

Yes, it is a speculation, a speculation even too speculative for Brownlee et al. because they do mention they could be some sort of "optically thick jet" (above the surface), which is at least one "mention" more than your speculation

Look at these images and try to see how they match your "bright nozzle" idea.
http://stardust.jpl.nasa.gov/photo/cometwild2.html
http://stardust.jpl.nasa.gov/highres/1097899fig7_s.jpg

From one of the references you quoted:

Quote:
Originally Posted by Brownlee et al
It is brighter than its surroundings and is seen in different images, ruling out the possibility that it is a phase effect or image artifact. In stereoimages, it has no height and appears to be an enhanced albedo spot on the surface, but it cannot be ruled out that the feature is not sunlight reflected off a short dust jet. There is an adjacent shadow-like dark spot that could be the shadow of an optically thick jet, but it appears to be the shadow of an adjacent small ridge. Several other bright spots are seen on the comet, some associated with irregular depressions. Whether these brightenings on an otherwise black surface are due to grain-size effects, condensed materials, or other processes is an intriguing question

Nope, no holes mentioned, if we stick to the facts and compare them to the Tempel 1 spots and patches http://deepimpact.jpl.nasa.gov/gallery/wipeout.html I think that electric arcs are a real possibility. Im waiting for the results of the Deep Impact spectrometer and I heard they plan to send the Stardust spacecraft after Comet Tempel 1 to image the crater. Might be a good moment to look at the dynamics of the bright spots.

Not dense enough to break the jet.

Duh.

By the way, you have not addressed this post:

Space craft are also subject to EDM, or "electrostatic discharges" as seen in this paper http://www.iop.org/EJ/article/0022-3...03/d207l3.html

I have no time to look for further evidence now, but I'll try to find some more relevant references.

Cheers.

[papageno]

Yes, it is a speculation, a speculation even too speculative for Brownlee et al. because they do mention they could be some sort of "optically thick jet" (above the surface), which is at least one "mention" more than your speculation

But less speculative than the EDM-idea, since comets are not made of conducting material and the voltages necessary to produce the electric arcs are not observed.

Look at these images and try to see how they match your "bright nozzle" idea.
http://stardust.jpl.nasa.gov/photo/cometwild2.html
http://stardust.jpl.nasa.gov/highres/1097899fig7_s.jpg

Hard to tell.
Besides your opinion that they don't look like nozzles, what physical argument do you have to exclude such possibility?

From one of the references you quoted:

It is brighter than its surroundings and is seen in different images, ruling out the possibility that it is a phase effect or image artifact. In stereoimages, it has no height and appears to be an enhanced albedo spot on the surface, but it cannot be ruled out that the feature is not sunlight reflected off a short dust jet. There is an adjacent shadow-like dark spot that could be the shadow of an optically thick jet, but it appears to be the shadow of an adjacent small ridge. Several other bright spots are seen on the comet, some associated with irregular depressions. Whether these brightenings on an otherwise black surface are due to grain-size effects, condensed materials, or other processes is an intriguing question

Nope, no holes mentioned, if we stick to the facts and compare them to the Tempel 1 spots and patches http://deepimpact.jpl.nasa.gov/gallery/wipeout.html I think that electric arcs are a real possibility.

How exactly?

The bright patches in the image may consist of very smooth and reflective material...

Im waiting for the results of the Deep Impact spectrometer and I heard they plan to send the Stardust spacecraft after Comet Tempel 1 to image the crater. Might be a good moment to look at the dynamics of the bright spots.


Space craft are also subject to EDM, or "electrostatic discharges" as seen in this paper http://www.iop.org/EJ/article/0022-3...03/d207l3.html

Satellite solar arrays are likely to be charged by the space environment up to a discharging threshold level, resulting in electrostatic discharges. Electrostatic discharges are phenomena known to cause temporary anomalies, mainly electromagnetic disturbances. Such discharges are studied experimentally in this paper on laboratory samples made of zinc or silver, and on real solar cell samples. Spectroscopic data show for all these samples the presence of eroded metal vapours, and microscopic photographs confirm the local melting of the electrode, even for low values of the capacitors (10 nF and 330 pF) used in the electrical circuit.

What exactly is so EDM about these experiments?
They talk about electromagnetic disturbances, and had to use microsops to see the damage on the samples.
Where are the craters and jets of material?

My questions were:

So, where is the evidence that the surface of comets are conductive enough?
The space probes we sent out are made of metal: where is the EDM?

[...]

Do you remember that the Solar Wind is macroscopically neutral?
How do you build up a voltage between the comet's surface and the environment?

I have no time to look for further evidence now, but I'll try to find some more relevant references.

Further evidence?
You have not presented yet any evidence in support of the EDM-idea, nor have you addressed my questions about it.

[VanderL]

But less speculative than the EDM-idea, since comets are not made of conducting material and the voltages necessary to produce the electric arcs are not observed.

Ok, since you seem to know exactly what comets are made of, could you tell me, besides the exact composition, what the conductivity of a comet is and how this excludes any EDM activity? How would you observe a voltage?

Quote:
Originally Posted by VanderL
Look at these images and try to see how they match your "bright nozzle" idea.
http://stardust.jpl.nasa.gov/photo/cometwild2.html
http://stardust.jpl.nasa.gov/highres/1097899fig7_s.jpg

Hard to tell.
Besides your opinion that they don't look like nozzles, what physical argument do you have to exclude such possibility?

No, you answer the question, it is your claim. It it least has the advantage that it supposes a connection between the bright spots and jets, something that hasn't been addressed by the professionals, to my knowledge.

How exactly?

Well, if it was known exactly, we wouldn't be discussing this in the ATM section.

What exactly is so EDM about these experiments?
They talk about electromagnetic disturbances, and had to use microsops to see the damage on the samples.
Where are the craters and jets of material?

Dismissing the information as irrelevant isn't going to change the fact that discharging happens to spacecraft. Why wouldn't it happen on other objects moving around in space? You're being dismissive.

My questions were:

Quote:
Originally Posted by papageno
So, where is the evidence that the surface of comets are conductive enough?
The space probes we sent out are made of metal: where is the EDM?

[...]

Do you remember that the Solar Wind is macroscopically neutral?
How do you build up a voltage between the comet's surface and the environment?

1. It would all depend on the strength of the electric fields, if they are strong enough, EDM happens to many different kinds of material.

2. I provided evidence for discharges on spacecraft, so we do have EDM (or something very similar) on spacecraft, discussion closed.

3. Building up a voltage difference between a comet and it's surroundings is because it moves radially wrt the Sun. But you already knew this and it brings us back to the assumption of a weak radial electric field centered on the Sun.

Further evidence?
You have not presented yet any evidence in support of the EDM-idea, nor have you addressed my questions about it.

Yes I did. While most of your questions are pertinent, I interpret some of your comments as unnessarily dismissive.

Cheers.

[iantresman]

How do you build up a voltage between the comet's surface and the environment?

One way, is the same way that the dark side of the Moon's surface gets charged, which I have previous referenced. Not bad for a macroscopically neutral Solar Wind.

Not only that, this charging appear to cause lunar dust to levitate, and even causes "fountains" [see A Dynamic Fountain Model for Dust in the Lunar Exosphere (2005)], which bears an uncanny resemblance to "plasma plumes", and such fountain-like plumes have even been applied to comets.

Word association or common causes?

Regards,
Ian Tresman

[Nereid]

One way, is the same way that the dark side of the Moon's surface gets charged, which I have previous referenced. Not bad for a macroscopically neutral Solar Wind.

Not only that, this charging appear to cause lunar dust to levitate, and even causes "fountains" [see A Dynamic Fountain Model for Dust in the Lunar Exosphere (2005)], which bears an uncanny resemblance to "plasma plumes", and such fountain-like plumes have even been applied to comets.

Word association or common causes?

Regards,
Ian Tresman

At an OOM level, does the hypothesis of 'common cause' seem plausible?

[papageno]

One way, is the same way that the dark side of the Moon's surface gets charged, which I have previous referenced. Not bad for a macroscopically neutral Solar Wind.

So, where are the electric discharges causing jets of material, such as in EDM?
Is the surface charging enough to produce such discharges?

Not only that, this charging appear to cause lunar dust to levitate, and even causes "fountains" [see A Dynamic Fountain Model for Dust in the Lunar Exosphere (2005)],...

From the Apollo era there is much evidence to show that lunar horizon glow observed at the terminator is caused by sunlight scattered by dust grains originating from the surface. The dust grains and lunar surface are electrically charged by the moon's interaction with the local plasma environment and the photoemission of electrons due to solar UV and X-rays. This causes the like-charged surface and dust particles to repel each other, and creates a near-surface electric field. Previous models have explained dust observations at ~10 cm above the surface, by suggesting that charged grains "levitate" in the local electric field; however this does not explain observations at ~1 km altitude. In order to explain the high-altitude dust observations, we propose a dynamic "fountain" model in which charged dust grains follow ballistic trajectories, subsequent to being accelerated upwards through a narrow sheath region by the surface electric field. The affect of different surface electric field profiles and adhesion of grains to the surface is also investigated. These dust grains will affect the optical quality of the lunar environment for astronomical observations and interfere with exploration activities.

So, where are the electric discharges causing jets of material, such as in EDM?

... which bears an uncanny resemblance to "plasma plumes",...

The combined observations allowed construction of an underlying picture of the processes during space storms, when the Earth's magnetic field is buffeted by hot plasma from the sun. As the solar plasma blows by, it generates an electric field that is transmitted to the plasmasphere and ionosphere. This electric field propels the ionospheric and the plasmaspheric plasma out into space. For the first time, scientists can directly connect the plasma observed in the ionosphere with the plasmasphere plumes that extend many thousand of kilometers into space.

So, where are the electric discharges causing jets of material, such as in EDM?
And what is the "maintream" view of the interaction between Solar Wind and comets?

...and such fountain-like plumes have even been applied to comets.

Computer processing of five plates of Comet Halley taken during the 1910 apparition shows that on May 24 strong asymmetric (with respect to the tail axis) fountain-like parabolic plumes had developed on the sunward side of the nucleus. Visual observations showed that after an initial fading while passing in front of the sun, the brightness increased to about magnitude 1. On the plates taken May 31, the nucleus is clearly divided into at least three parts of nearly equal brightness. However, the last plate on June 3 shows a symmetrical coma with a small stellar-like nucleus.

So, where are the electric discharges causing jets of material, such as in EDM?

Word association or common causes?

You did not address my other questions:

So, where is the evidence that the surface of comets are conductive enough?
The space probes we sent out are made of metal: where is the EDM?

[papageno]

Ok, since you seem to know exactly what comets are made of, could you tell me, besides the exact composition, what the conductivity of a comet is and how this excludes any EDM activity? How would you observe a voltage?

You are trying to shift the burden of proof on me.
You and iantresman have been claiming:

Electric Unvierse proponents suggested that comets were not icy snowballs, because they felt that that model was inadequate. They felt that electric discharge machining (EDM) was involved in producing jets and a comet's tail.

These arcs are the so called "bright spots" or "bright patches" seen in close ups of comets (Wild 2 and Tempel 1), I'll dig up the references and the comments of what they are thought to be ( I mean, the non-arc explanation).

I am still waiting for both of you to support this idea that an EDM-like effect is responsible for jets from comets and that the bright spots observed in some picture are electic arcs.
So far, neither of you has been able to show the evidence to support an analogy with EDM, let alone the actual EDM-like mechanism.

No, you answer the question, it is your claim.

It started with this:

This nozzle opening is exactly missing from all the observations thusfar; pure speculation. Maybe Rosetta will be close enough to image such a nozzle, but be prepared to find a "bright spot" staring back at the camera, and no "nozzle" in sight.

And I tried to point out a possibility you might have missed:

The idea that a hole in a dark surface might appear as bright spot seems to be alien to you.

because a hole in a hardened surface can work as a nozzle.

It it least has the advantage that it supposes a connection between the bright spots and jets, something that hasn't been addressed by the professionals, to my knowledge.

Remember what you quoted?

Sekanina et al:
Triangulation of 20 jets shows that 2 emanate from the nucleus dark side and 16 emanate from sources that are on slopes where the Sun’s elevation is greater than predicted from the fitted triaxial ellipsoid. Seven sources, including five in the Mayo depression, coincide with relatively bright surface spots.

7 out of 20 jets seemed to be correlated to bright spots.
When you suppose that there is a connection, and you cannot support the viability of the mechanism (EDM) for such connection, you are just jumping to conclusions.

Well, if it was known exactly, we wouldn't be discussing this in the ATM section.

But you are not bringing anything in support of your "I think that electric arcs are a real possibility", except for your sympathy for EU/PC points of view.

Dismissing the information as irrelevant isn't going to change the fact that discharging happens to spacecraft. Why wouldn't it happen on other objects moving around in space? You're being dismissive.

I explained why I think those references are not relevant: the samples where electrically conductive and the damage done was microscopic.
Since you brought it up, it is up to you to show how that reference is relevant to jets from comets.

1. It would all depend on the strength of the electric fields, if they are strong enough, EDM happens to many different kinds of material.

Electrically conducting material.
So,

So, where is the evidence that the surface of comets are conductive enough?

How do you build up a voltage between the comet's surface and the environment?

2. I provided evidence for discharges on spacecraft, so we do have EDM (or something very similar) on spacecraft, discussion closed.

Do you mean, those experiments with electrically conducting samples that showed microscopic damage and no jets of material?
So,

The space probes we sent out are made of metal: where is the EDM?

Where are the jets of material from our space probes?

3. Building up a voltage difference between a comet and it's surroundings is because it moves radially wrt the Sun. But you already knew this and it brings us back to the assumption of a weak radial electric field centered on the Sun.

iantresman came up with the idea that a comet charges up in the interplanetary plasma, like the Moon's surface does.
But I still see no sort of quantitative estimate to support this EDM-idea.

You have not presented yet any evidence in support of the EDM-idea, nor have you addressed my questions about it.

Yes I did. While most of your questions are pertinent, I interpret some of your comments as unnessarily dismissive.

Where have you shown that bright spots on comets are electric arcs?
Where have you shown that a voltage can build up between a comet and the environment?
Where have you shown that this voltage is strong enough to produce eletric arcs that give rise to jets of material from the comet?

[tusenfem]

here is an interesting paper explaining the levitating dust on the moon. Unfortunately they do not give a value for the total charge of the moon (or my scanning of the paper was incorrect).

But our faithful ADS is always there. Here is an abstract of a paper on the Lunar Prospector, looking for charges > 500 V on the surface of the moon. From the abstract:

We survey Lunar Prospector Electron Reflectometer measurements from times when the Moon was located in the geomagnetic tail, in order to characterize the occurrence of large (>500 V) negative lunar surface potentials, as identified by upward-going electron beams. We find that charging to these levels is rare, but that such charging events do occasionally occur in both sunlight and shadow.

But voltages are not all ofcourse. If we want to have EDM on the moon (which I greatly doubt will occur because of why EDM was invented and how it works) then we need strong electric fields to get the "spark". Also from the abstract:

Depending on the electric field scale height, significant electric fields of up to ~100 V/m may sometimes exist at the lunar surface.

I have a feeling that this is very insufficient to have EDM on the surface of the moon.

So now I have done my job, now let's see if one of the proponents can give values for comet charges AND an estimate for the electric field that is needed to do EDM.

[VanderL]

You are trying to shift the burden of proof on me.
You and iantresman have been claiming:
I am still waiting for both of you to support this idea that an EDM-like effect is responsible for jets from comets and that the bright spots observed in some picture are electic arcs.
So far, neither of you has been able to show the evidence to support an analogy with EDM, let alone the actual EDM-like mechanism.


It started with this:
And I tried to point out a possibility you might have missed:
because a hole in a hardened surface can work as a nozzle.


Remember what you quoted?
7 out of 20 jets seemed to be correlated to bright spots.
When you suppose that there is a connection, and you cannot support the viability of the mechanism (EDM) for such connection, you are just jumping to conclusions.


But you are not bringing anything in support of your "I think that electric arcs are a real possibility", except for your sympathy for EU/PC points of view.



I explained why I think those references are not relevant: the samples where electrically conductive and the damage done was microscopic.
Since you brought it up, it is up to you to show how that reference is relevant to jets from comets.



Electrically conducting material.
So,


Do you mean, those experiments with electrically conducting samples that showed microscopic damage and no jets of material?
So, Where are the jets of material from our space probes?


iantresman came up with the idea that a comet charges up in the interplanetary plasma, like the Moon's surface does.
But I still see no sort of quantitative estimate to support this EDM-idea.


Where have you shown that bright spots on comets are electric arcs?
Where have you shown that a voltage can build up between a comet and the environment?
Where have you shown that this voltage is strong enough to produce eletric arcs that give rise to jets of material from the comet?

Papageno,

I'm going to decline giving you answers to any of your questions (however pertinent) until you drop the accusatory tone, admit that the reference I posted shows that spacecraft undergo discharging effects and acknowledge that you started the line of reasoning for a hole in a comet's surface. I want the discussion to be fair and open and not waste my time endlessly going in circles and having to answer incorrect claims that I didn't do enough. I know that the model needs a lot more detail on a lot of points, but harrassing people doesn't help. I cannot produce the exact numbers you are after, but I can try to answer questions, dig up references and discuss predictions/developments.

Cheers.

[VanderL]

here is an interesting paper explaining the levitating dust on the moon. Unfortunately they do not give a value for the total charge of the moon (or my scanning of the paper was incorrect).

But our faithful ADS is always there. Here is an abstract of a paper on the Lunar Prospector, looking for charges > 500 V on the surface of the moon. From the abstract:



But voltages are not all ofcourse. If we want to have EDM on the moon (which I greatly doubt will occur because of why EDM was invented and how it works) then we need strong electric fields to get the "spark". Also from the abstract:



I have a feeling that this is very insufficient to have EDM on the surface of the moon.

So now I have done my job, now let's see if one of the proponents can give values for comet charges AND an estimate for the electric field that is needed to do EDM.

Thanks tusenfem,

This might be helpful, I want to say that the effect of levitation can be viewed as the weakest form of EDM. If the EU model is true, the charging/discharging of moondust is the weak analogy of EDM on comets.

Cheers.

[papageno]

I'm going to decline giving you answers to any of your questions (however pertinent) until you drop the accusatory tone,...

Style over substance?
Not a good excuse.

....admit that the reference I posted shows that spacecraft undergo discharging effects...

I never said that discharges do not happen on spacecrafts.
I simply explained that that reference is not relevant to cometary jets.
Since you brought up the reference, it is up to you to show how it is relevant, but you did not do so.

... and acknowledge that you started the line of reasoning for a hole in a comet's surface.

I simply inserted an observation in your line of "reasoning" that identified bright spots on comets with electric arcs.
In my opinion you do not realize that a hole in a hardened surface can work as a nozzle, consistent with the observation of cometary jets (as described by Tim Thompson).
Nor is my idea that bright spots are the material beneath the surface "peering" through less supported than your idea that the bright spots are electric arcs.

I want the discussion to be fair and open and not waste my time endlessly going in circles and having to answer incorrect claims that I didn't do enough.

It is in plain sight that you have not done enough.
Since you started supporting the EDM idea for cometary jets, you have not supported it with sound reasoning or pertinent evidence.

It is not fair that you keep avoiding the questions whose answers are critical to decide the validity of this EDM idea.
It is painfully obvious that you did not accept this idea because you examined the evidence and found it consistent with it, as opposed to the "mainstream" explanation.
Instead to jumped on it because EU/PC proponents came up with it.
There was no reasoning behind your acceptance of it: just a leap of faith.

I know that the model needs a lot more detail on a lot of points, but harrassing people doesn't help.

I asked those questions at the beginning, and I am still waiting for the answer.

I cannot produce the exact numbers you are after, but I can try to answer questions, dig up references and discuss predictions/developments.

You already said that at the beginning.
So, show us that te surface of comets are electrically conducting, that a voltage builds up between the surface and the environment, that this voltage is high enough to produce electric arcs, that these arcs produce the observed jets of material from the comet and coincide with the bright spots in the pictures.
This is simply a summary of the claims you made about this topic, and for which you have neither provided evidence nor quantitative estimates (at the OOM level, not "exact" numbers)

[VanderL]

I never said that discharges do not happen on spacecrafts.
I simply explained that that reference is not relevant to cometary jets.
Since you brought up the reference, it is up to you to show how it is relevant, but you did not do so.

I did, you asked for evidence that spacecraft also undergo EDM; the important part of the mechanism is discharging. The reference shows this, so it is relevant.

Why are you changing to "I never said that discharges do not happen on spacecrafts."? If it happens to spacecraft it can happen to comets. Comets will have different electrical properties than spacecraft, but that doesn't exclude discharging. As Ian showed (and tusenfem elaborated on) even the Moon can be conductive enough to produce a very weak EDM-like mechanism. So why not comets as well?

Stop accusing me of not answering or at least addressing your questions. I'm saying that if electric arcs produce jets, they should be bright (give off light, not just reflect it), they should be close to the surface, mostly found on higher elevations and on the edges of cliffs/scarps, they should have structure and show dynamics and correlate to jets.
You might want to see more clear evidence (so do I), but comets aren't very well studied in "electrical" terms. There's spectroscopic data to come from the Tempel 1 bright spots, and I hope data on the plasma conditions surrounding Tempel 1 will become available. A time-lapse movie of bright spots and how the comet's surface changes over time would help. The existence of the bright spots have to be explained one way or another, I think that the images (especially of the Wild 2 bright spots) are clear enough to suppose they could be electric arcs, as supposed in the electric comet model, so why are you so adamant I should provide OOM's without any proper data? How does one determine a comet's electrical conductivity without measuring it? To me that is more like badgering, and demanding answers that aren't available yet (or at least I don't know of any better data).

[papageno]

I did, you asked for evidence that spacecraft also undergo EDM; the important part of the mechanism is discharging. The reference shows this, so it is relevant.

I brought up spacecrafts, because, if cometary jets are the result of EDM-like effects, then it is more likely to happen with mostly metallic objects, such as the probes.
But EDM-like effects on spacecrafts are not proof of the same for comets, since comets are not mostly made of conducting material.

That reference shows the electrostatic discharge, but not the machining in EDM.
So, where is the "machining", where are the jets of material from spacecrafts as a consequence of electric arcs?
Local melting in spots less than 100 micron wide are not machining.

Why are you changing to "I never said that discharges do not happen on spacecrafts."?

You said: "admit that the reference I posted shows that spacecraft undergo discharging effects", as if I ever said that discharges do not happen on spacecrafts.
I never said that.

If it happens to spacecraft it can happen to comets.

You keep missing the point.
Spacecrafts and comets are not exactly the same.
Showing that EDM happens on spacecrafts is only one step: you have to show that the same conditions occur for comets.
But have done neither: you simply stated it without support.

Comets will have different electrical properties than spacecraft, but that doesn't exclude discharging.

Yet EDM requires the sample to be electrically conducting.
If it worked on insulating materials, do you think it would not be used?

As Ian showed (and tusenfem elaborated on) even the Moon can be conductive enough to produce a very weak EDM-like mechanism. So why not comets as well?

That was levitation of charged dust particles: that is nothing more exotic than Coulomb's law.

What you and iantresman claim is that electrostatic discharges on comets are responsible for the jets of material, which is not levitation of particles.
Therefore, iantresman reference, as fascinating as it is, is not relevant.

Stop accusing me of not answering or at least addressing your questions. I'm saying that if electric arcs produce jets, they should be bright (give off light, not just reflect it), they should be close to the surface, mostly found on higher elevations and on the edges of cliffs/scarps, they should have structure and show dynamics and correlate to jets.

Do you remember your claim?

These arcs are the so called "bright spots" or "bright patches" seen in close ups of comets (Wild 2 and Tempel 1), I'll dig up the references and the comments of what they are thought to be

I pointed out that even in the references you quoted, there was only a slight correlation between jets and bright spots (7 out of 20), yet for you the electric arcs ARE the bright spots.
Where is the evidence that supports this "are"?
You did not even build up a proper analogy between cometary jets and EDM, yet for you These arcs are the so called "bright spots".
So far only statements from you, but not even with a pair of pliers I could get from you relevant references or even a well-founded reasoning.

You might want to see more clear evidence (so do I), but comets aren't very well studied in "electrical" terms.

Now suddenly plasma is not electrical?
Because comets do interact with the Solar Wind.

There's spectroscopic data to come from the Tempel 1 bright spots, and I hope data on the plasma conditions surrounding Tempel 1 will become available. A time-lapse movie of bright spots and how the comet's surface changes over time would help.

How long do you think electric arcs last?

The existence of the bright spots have to be explained one way or another, I think that the images (especially of the Wild 2 bright spots) are clear enough to suppose they could be electric arcs, as supposed in the electric comet model, so why are you so adamant I should provide OOM's without any proper data?

First, the only bright spots I have seen referenced by you, were small points, with no discernible structure or form.
And I am still waiting for you to show how you identified them with electric arcs.
Second, if EU/PC model does not even provide an OOM estimates of the effects (which could be at least attempted), then for sure it is no better than "mainstream" models.
And this is the real question:

Why do we need an electric universe hypothesis? Why do we need an electric sun (or electric star) hypothesis? What is it about the observable universe, which can be convincingly shown to be in contradiction to standard, mainstream theory, to the extent that the new hypothesis is necessary to survive?

How does one determine a comet's electrical conductivity without measuring it?

Suddenly we have no idea about the electrical properties of ice and the other materials identified on comets?
If spectroscopic data and the probes gives us informations about the materials composing the comets, then we can at least attempt OOM estimates based on what we know of those materials here on Earth.
But I can tell you that a "dirty snowball" or a "snowy dirtball" will not have the electric properties of a metal (which is one of the conditions for EDM).

To me that is more like badgering, and demanding answers that aren't available yet (or at least I don't know of any better data).

Then you have to admit that your support of the EDM idea is not based on scientific arguments or reasoning.

[sol88]

VanderL

Great effort on trying to convert the heathens but alas no luck.

But i'm along the lines of the EU theory myself and had a few questions maybe someone could answer.

1) if comets can gain charge by moving thru the heliosphere then can't the sun "act like a comet" if it itself is moving thru interstella plasma and all the planets are along for the ride.

2) Could gamma ray bursts be evidence of interstella "lightning", Z-pinch star births or planetery births.

3) What would make the EU theory definitive in the eyes of the "Good ole boys"?

Hope the questions are not too nOOb like

This theory certainly opens up alot more possibities than the BB model.

Sol

[tusenfem]

Before we go on discussion EDM based on the wikipedia description, I think a proponent of this method should first show the details of this process, i.e. electric fields needed, material needed, conductivities needes, before we get that discussion is useless.
So either one of VanderL or Iantresman needs to show the details, as they propose that something developed to cut "uncuttable iron" can be expected in comet or on the moon.

[Nereid]

VanderL

Great effort on trying to convert the heathens but alas no luck.

But i'm along the lines of the EU theory myself and had a few questions maybe someone could answer.

1) if comets can gain charge by moving thru the heliosphere then can't the sun "act like a comet" if it itself is moving thru interstella plasma and all the planets are along for the ride.

2) Could gamma ray bursts be evidence of interstella "lightning", Z-pinch star births or planetery births.

3) What would make the EU theory definitive in the eyes of the "Good ole boys"?

Hope the questions are not too nOOb like

This theory certainly opens up alot more possibities than the BB model.

Sol

Welcome to BAUT, sol88!

Could I suggest that you take some time to read the BAUT rules, especially the part on this ATM section? You'll see that they're a little different from what you may be used to elsewhere.

In particular, proponents of an ATM idea (and from your post, you seem to be a proponent of the EU idea) must answer direct, relevant questions about that idea (in terms of what they post), in a timely fashion.

So, for example, you said "This theory [the EU idea] certainly opens up alot more possibities than the BB model." That is a very clear statement ("certainly", for example, leaves no room for ambiguity!), and I, or any other BAUT member, may choose to challenge your assertion. For example, I could ask you to defend your claim

• that it is a theory
• about the possibilities it opens up
• by sketching the outlines of the theory (in terms of equations, maths, numbers and stuff)
• and so on.

You can see that, in terms of the ATM rules, your first two questions are ones which an EU proponent needs to answer - that can either be you, or we could ask VanderL, Iantresman, or any other EU proponent still reading this thread to answer (of course, they could answer "that's not yet known", or "no EU proponent has worked anything like that out yet, to the best of my knowledge", or even "no, neither of those things is possible in the EU idea").

The last question is one that many BAUT members who've contributed to this thread have answered many times, going back over two years now: a good place to start would be some math, equations, numbers and stuff; in particular, some OOM (order of magnitude) estimates of the key parts of this idea, together with a demonstration that these are consistent with good experimental and observational data (at the OOM level).

Of course, that would only be a start, but at least it would represent a tremendous step forward in this thread.

I look forward to your next post with eager anticipation, and hope that you will provide some equations, math, numbers and stuff.

[VanderL]

I brought up spacecrafts, because, if cometary jets are the result of EDM-like effects, then it is more likely to happen with mostly metallic objects, such as the probes.
But EDM-like effects on spacecrafts are not proof of the same for comets, since comets are not mostly made of conducting material.

Good thinking about the spacecraft, you might want to take into consideration that the effects of EDM are either machining or deposition depending on the charge "sign".

That reference shows the electrostatic discharge, but not the machining in EDM..

There is no difference, imo, just in applied charge and the duration of the discharging.

So, where is the "machining", where are the jets of material from spacecrafts as a consequence of electric arcs?
Local melting in spots less than 100 micron wide are not machining.

Spacecraft are much smaller, so the charge buildup is smaller too, I don't remember any images of spacecraft that would show any jet-like structures (I think glow discharges would be more probable). I guess it should be possible to find evidence of space "weathering" effects on spacecraft and see if they look more like EDM. Btw, don't they coat spacecraft to protect the metal? Oh, and I remember a Tether experiment that ended in explosively broken tether, maybe they have some EDM effects to show.

You said: "admit that the reference I posted shows that spacecraft undergo discharging effects", as if I ever said that discharges do not happen on spacecrafts.
I never said that.

You think EDM and discharging is very different?

You keep missing the point.
Spacecrafts and comets are not exactly the same.
Showing that EDM happens on spacecrafts is only one step: you have to show that the same conditions occur for comets.
But have done neither: you simply stated it without support.

No I don't, the reasoning is simple. If it happens to spacecraft, it is logical that is happens to comets too. The support comes from looking for evidence of EDM on comets, the surface of a comet, the jets, the dust, the bright spots, the ions around comets, the X-rays they can all logically be fit into a discharge model.

Yet EDM requires the sample to be electrically conducting.
If it worked on insulating materials, do you think it would not be used?

Maybe some conductivity is required, but I don't know what threshold value for conductivity is necessary to get the process going. It would in mind also be possible that on a comet's surface some (layers or veins of)minerals are conducting and others are not, focussing the discharging process.

That was levitation of charged dust particles: that is nothing more exotic than Coulomb's law.

Yeah, so?

What you and iantresman claim is that electrostatic discharges on comets are responsible for the jets of material, which is not levitation of particles.
Therefore, iantresman reference, as fascinating as it is, is not relevant.

I disagree, charging of moondust is evident, the relevance is in the analogy, weak effects on the Monn, much stronger effects on comets.

Do you remember your claim?
I pointed out that even in the references you quoted, there was only a slight correlation between jets and bright spots (7 out of 20), yet for you the electric arcs ARE the bright spots.
Where is the evidence that supports this "are"?
You did not even build up a proper analogy between cometary jets and EDM, yet for you These arcs are the so called "bright spots".

Ok, strong wording, I should have said "possibly" and 7 out of 20 means 7 proven, maybe the rest was too difficult to determine (darkside maybe?) or the spots were too small to see. I can't tell from the publication. I interpret it as meaning at least 7 out of 20.

So far only statements from you, but not even with a pair of pliers I could get from you relevant references or even a well-founded reasoning.

Now suddenly plasma is not electrical?
Because comets do interact with the Solar Wind.

Sure, but I haven't seen these data from Deep Impact, nor from Wild 2.

How long do you think electric arcs last?

Long, maybe they are in place for months, although they should be moving around on the surface.

The rest of the post will have to wait.

Cheers.

[iantresman]

Before we go on discussion EDM based on the wikipedia description, I think a proponent of this method should first show the details of this process, i.e. electric fields needed, material needed, conductivities needes, before we get that discussion is useless.
So either one of VanderL or Iantresman needs to show the details, as they propose that something developed to cut "uncuttable iron" can be expected in comet or on the moon.

Although slightly different phenomenon, lightning is known to cause physical damage to materials it strikes. On the other hand, we've all seen the effect of a mild electrostatic charge to a container of polystyrene beads.

As for details, I've been unable to find any. Even EDM details are hard to come by.

Regards,

[papageno]

I brought up spacecrafts, because, if cometary jets are the result of EDM-like effects, then it is more likely to happen with mostly metallic objects, such as the probes.
But EDM-like effects on spacecrafts are not proof of the same for comets, since comets are not mostly made of conducting material.

Good thinking about the spacecraft, you might want to take into consideration that the effects of EDM are either machining or deposition depending on the charge "sign".

This does not address my points: where are the jets of material from spacecrafts, and does the same happen to comets?

That reference shows the electrostatic discharge, but not the machining in EDM.

There is no difference, imo, just in applied charge and the duration of the discharging.

The difference is quantitative: that reference replicated conditions satellites and space probes are exposed to, and showed that the solar panels can be damaged by electrostatic discharges.
The experiments did not result in EDM of the samples. If you want to use it as pertinent reference, you have to provide well-founded quantitative estimates showing that the effects are scaled up for space probes in interplanetary space.

And this would still not be enough to support the EDM idea for cometary jets.

So, where is the "machining", where are the jets of material from spacecrafts as a consequence of electric arcs?
Local melting in spots less than 100 micron wide are not machining.

Spacecraft are much smaller, so the charge buildup is smaller too, I don't remember any images of spacecraft that would show any jet-like structures (I think glow discharges would be more probable). I guess it should be possible to find evidence of space "weathering" effects on spacecraft and see if they look more like EDM. Btw, don't they coat spacecraft to protect the metal? Oh, and I remember a Tether experiment that ended in explosively broken tether, maybe they have some EDM effects to show.

You did not read that reference, did you?
You cannot bluff your way out of this by handwaving.

The tests were carried out in a stainless steel vacuum chamber 0.7 m in diameter and 0.5 m in height...

[...]

The samples used during the experiments were real solar cell samples (solar cells made of silicium with silver connectors above and below the cell, protected by a cover glass and placed above a Kapton film) and laboratory samples made in order to mimic this typical cell geometry (metallic sheets made of silver or zinc rest on an epoxy plate, and are covered by a Teflon film having a thickness of 125 µm and aluminized on its back side).

[...]

The spectroscopic data indicates that the electrostatic discharges produce metal vapour plasma. Zinc lines were identified for the zinc electrode samples, silver lines for the silver electrode samples. Silver lines were also identified for the solar cell sample, showing that the silver coating on the rear side of the cell is vaporized during the electrostatic discharge. The current and the electron emission in vacuum arcs are concentrated in small areas of the cathode surface called cathode spots. The SEM recordings effectively show erosion craters very typical in shape and size (~µm diameter) to spots described in the literature. These zones are the site of strong melting and vaporization of the cathode material resulting in locally but important electrode material erosion and degradation [4]-[7]. So the metallic electrode (or the silver connector for the real solar cells) acts as the cathode of the discharge.

[...]

However, these vacuum arcs did not last more than 50 µs and so can be called aborted arcs. These results show that the so-called electrostatic discharges occurring on solar arrays produce permanent damages on the cells and not only temporary anomalies.

You said: "admit that the reference I posted shows that spacecraft undergo discharging effects", as if I ever said that discharges do not happen on spacecrafts.
I never said that.

You think EDM and discharging is very different?

Electric
Discharge
Machining
There is a reason for adding Machining to Electric Discharge.
So, EDM and discharge are different.

You keep missing the point.
Spacecrafts and comets are not exactly the same.
Showing that EDM happens on spacecrafts is only one step: you have to show that the same conditions occur for comets.
But have done neither: you simply stated it without support.

No I don't, the reasoning is simple. If it happens to spacecraft, it is logical that is happens to comets too.

It would be if spacecrafts and comets were the same.
But you have not provided anything to support this.

The support comes from looking for evidence of EDM on comets, the surface of a comet, the jets, the dust, the bright spots, the ions around comets, the X-rays they can all logically be fit into a discharge model.

They are more consistent with the "mainstream" model, since comets are not made of metal, as required in EDM.

Yet EDM requires the sample to be electrically conducting.
If it worked on insulating materials, do you think it would not be used?

Maybe some conductivity is required, but I don't know what threshold value for conductivity is necessary to get the process going.

So, you don't know the conditions necessary to have EDM.
Yet you are sure that it happens on comets, even though you cannot quantify their conductivity or even show that they are metallic.

It would in mind also be possible that on a comet's surface some (layers or veins of)minerals are conducting and others are not, focussing the discharging process.

Grasping at straws?
Nature does not care what in your mind is possible.

That was levitation of charged dust particles: that is nothing more exotic than Coulomb's law.

Yeah, so?

You don't see the difference between levitation of particles and electric discharge?
Levitation of charged dust particles does not imply electric arcs, formation of craters and jets of materials.

What you and iantresman claim is that electrostatic discharges on comets are responsible for the jets of material, which is not levitation of particles.
Therefore, iantresman reference, as fascinating as it is, is not relevant.

I disagree, charging of moondust is evident, the relevance is in the analogy, weak effects on the Monn, much stronger effects on comets.

What did you say above?

Spacecraft are much smaller, so the charge buildup is smaller too...

Comets are much smaller than the Moon, so where are your calculations showing that the charge build-up on a comet is enough to make dust levitate.
Then you should explain in detail how this idea is relevant to the idea that electric arcs produce cometary jets.

Do you remember your claim?
I pointed out that even in the references you quoted, there was only a slight correlation between jets and bright spots (7 out of 20), yet for you the electric arcs ARE the bright spots.
Where is the evidence that supports this "are"?
You did not even build up a proper analogy between cometary jets and EDM, yet for you These arcs are the so called "bright spots".

Ok, strong wording, I should have said "possibly" and 7 out of 20 means 7 proven, maybe the rest was too difficult to determine (darkside maybe?) or the spots were too small to see. I can't tell from the publication. I interpret it as meaning at least 7 out of 20.

Backpedalling?
You seemed to be pretty confident when you jumped from a correlation between bright spots and some of the jets to: These arcs are the so called "bright spots".

Now suddenly plasma is not electrical?
Because comets do interact with the Solar Wind.

Sure, but I haven't seen these data from Deep Impact, nor from Wild 2.

And how did you reach the conclusion that comets charge up?

How long do you think electric arcs last?

Long, maybe they are in place for months, although they should be moving around on the surface.

And somehow we keep missing them, even though we have probes dedicated to comets.
By the way, the reference you are so fond of, speaks of discharges that last about 50 microseconds.

The rest of the post will have to wait.

As a reminder:

First, the only bright spots I have seen referenced by you, were small points, with no discernible structure or form.
And I am still waiting for you to show how you identified them with electric arcs.

You should have done this when you claimed that These arcs are the so called "bright spots".

Suddenly we have no idea about the electrical properties of ice and the other materials identified on comets?
If spectroscopic data and the probes gives us informations about the materials composing the comets, then we can at least attempt OOM estimates based on what we know of those materials here on Earth.
But I can tell you that a "dirty snowball" or a "snowy dirtball" will not have the electric properties of a metal (which is one of the conditions for EDM).

You should have dealt with this problem, before starting to support the EDM idea.

So far, you have consistently dodged the issues that come up before the conclusion that cometary jets have an EDM origin can be reached.
The fact that you still cannot address those issues, is a clear sign that your support to this EDM idea is not a result of reasoning and physical arguments, but simply a leap of faith due to your sympathy for EU/PC ideas.

Stop wasting our time and address the issues in a scientifically appropriate manner (which includes includes withdrawal of unsupported claims).

[papageno]

Although slightly different phenomenon, lightning is known to cause physical damage to materials it strikes. On the other hand, we've all seen the effect of a mild electrostatic charge to a container of polystyrene beads.

As for details, I've been unable to find any. Even EDM details are hard to come by.

You don't need details to do OOM estimates: you have references for charging in interplanetary space and for compositions of comets.
You can estimate if electric arcs can occur and how strong they are.

But so far you have not even established a qualitative analogy between EDM and cometary phenomena.

[sol88]

Thanks Nereid for your warm welcome

I'll step in on the spacecraft do not discharge debate first up.

papageno:wrote

This does not address my points: where are the jets of material from spacecrafts, and does the same happen to comets?

The space shuttle was caught by a discharge that it could not sustain into EDM territory because it kinda blew up instead.

S.F. man's astounding photo mysterious purple streak is shown hitting Columbia 7 minutes before it disintegrated

Link http://www.weatherwars.info/index.ph...ear=&arcmonth=

And the space tether experiment, I think this definitively shows a charge build up in space

The nature of the break suggested it was not caused by excessive tension, but rather that an electric current had melted the tether.

Link http://www-istp.gsfc.nasa.gov/Education/wtether.html


Should at least establish that a charge can build up in space, as for figures, well I’m not a professional and only have access to the same material that most of you do i.e. the internet

As for spacecraft EDM, what would happen if you sent it out past Pluto then returned it at a steep angle to the ecliptic over the sun poles at around the same speed as a comet?? Would it gain a charge that would be sufficient enough for it discharge ?

How are X-rays produced by ice volcanoes and icy,dirty,fluffy comets? How is Io's "dust plume" accelerated to 300kps in narrow streams while some falls back radialy around the caldera?

[tusenfem]

Although slightly different phenomenon, lightning is known to cause physical damage to materials it strikes. On the other hand, we've all seen the effect of a mild electrostatic charge to a container of polystyrene beads.

As for details, I've been unable to find any. Even EDM details are hard to come by.

Regards,

I would advise to go to the german wiki page on EDM there is a link there to www.erosion.de where they list a looooong list of EDM research. Just click on "EDM links" and then on "Forschung".

[tusenfem]

And the space tether experiment, I think this definitively shows a charge build up in space

The tether experiment works on a totally different mechanism. It does not show a charge build up in space, but generates a voltage drop over the tether because of the VxB electric field.

Should at least establish that a charge can build up in space, as for figures, well I’m not a professional and only have access to the same material that most of you do i.e. the internet

Just a question. You say you are not a professional. What is your training if any, and what makes you decide that the EU is correct?

[VanderL]

This does not address my points: where are the jets of material from spacecrafts, and does the same happen to comets?



The difference is quantitative: that reference replicated conditions satellites and space probes are exposed to, and showed that the solar panels can be damaged by electrostatic discharges.
The experiments did not result in EDM of the samples. If you want to use it as pertinent reference, you have to provide well-founded quantitative estimates showing that the effects are scaled up for space probes in interplanetary space.

And this would still not be enough to support the EDM idea for cometary jets.

You did not read that reference, did you?
You cannot bluff your way out of this by handwaving.

Electric
Discharge
Machining
There is a reason for adding Machining to Electric Discharge.
So, EDM and discharge are different.

It would be if spacecrafts and comets were the same.
But you have not provided anything to support this.

They are more consistent with the "mainstream" model, since comets are not made of metal, as required in EDM.

So, you don't know the conditions necessary to have EDM.
Yet you are sure that it happens on comets, even though you cannot quantify their conductivity or even show that they are metallic.

Grasping at straws?
Nature does not care what in your mind is possible.

You don't see the difference between levitation of particles and electric discharge?
Levitation of charged dust particles does not imply electric arcs, formation of craters and jets of materials.

What did you say above?
Comets are much smaller than the Moon, so where are your calculations showing that the charge build-up on a comet is enough to make dust levitate.
Then you should explain in detail how this idea is relevant to the idea that electric arcs produce cometary jets.

Backpedalling?
You seemed to be pretty confident when you jumped from a correlation between bright spots and some of the jets to: These arcs are the so called "bright spots".

And how did you reach the conclusion that comets charge up?

And somehow we keep missing them, even though we have probes dedicated to comets.
By the way, the reference you are so fond of, speaks of discharges that last about 50 microseconds.

As a reminder:
You should have done this when you claimed that These arcs are the so called "bright spots".

You should have dealt with this problem, before starting to support the EDM idea.

So far, you have consistently dodged the issues that come up before the conclusion that cometary jets have an EDM origin can be reached.
The fact that you still cannot address those issues, is a clear sign that your support to this EDM idea is not a result of reasoning and physical arguments, but simply a leap of faith due to your sympathy for EU/PC ideas.

Stop wasting our time and address the issues in a scientifically appropriate manner (which includes includes withdrawal of unsupported claims).

Papageno,

I've totally had it with you, you are constantly questioning my honesty and integrity ("You did not read that reference, did you?
You cannot bluff your way out of this by handwaving"). I will answer questions if you do so politely. I'm supposed to give timely answers, and I expect from you to treat me with some respect. I am not trying to dodge anything, we've had a similar argument before, and yes, I'm not trained in physiscs, but that doesn't mean I can't try and argue some points. This is not a science journal, so you cannot expect the same standards.
The claim of EDM is logical (but only experiments will prove anything); if spacecraft can show discharge damage why not comets. Why you cannot see a similarity between levitation of charged moondust and EDM is beyond me, if weak electrical interactions can move small particles from a surface why can't the same process, scaled up, not be similar to EDM? I'll stop wasting my time answering your questions until you show some politeness.