Electric Comet numbers

[Noli Me Tangere]

Of course, Wikipedia 'forgot' to tell us, like the original article does, that this is what the observers estimate, based on the current assumptions:

The assumptions used were that the laws of physics are correct, i.e. the radiation spectrum emitted by matter can be used to calculate the mass of the matter.

I am at loss to imagine how, observing what kind of matter emits the radiation, one can determine HOW MUCH of this matter you have. Suppose, for example, we measure the spectrum of radiation of the matter from the surface of the moon, and I mean the whole matter from the surface. How can you tell from these measurements the mass of the moon? Afer all, if we translate this to the earth, the earth is supposed to have crust, mantle, inner and outer core (if we stick to the mainstream descriptions). I hope you don't mean that you can measure the radiation spectrum of the inner core so you can determine its mass.

The Swift observatory measured the spectrum of the ejected material and thus the amount of water. I do not know what observed the dust (the Science article is not accessible).

Once again, IF the matter whose spectrum is measured is removed by EDM (like EU say it does) then it IS no water that is ejected, so the calculations based on the amount of water are false/ irrelevant.

Observations also revealed that the comet was about 75% empty space, and one astronomer compared the outer layers of the comet to the same makeup of a snow bank.[11]

I think that these 'observations' were made this way (if you have informations otherwise please share them; it is only my supposition at work here):
1. The average density of the materials found according to the spectral analysis is on earth about 2.5
2. The mass of the comet calculated with the density * volume formula is four times the mass calculated using the orbital parameters (which gives a density of 0.62).
3. The conclusion is that the comet contains these materials, but they are porous, or the comet is somehow 75% empty.

I think that the observations are the original measurement of the density of Tempel 1 plus the composition of the material ejected by the impact.

I put 'observations' in quotes because there were no direct observations on the density of the comet, only calculations using the orbital parameters, spectrum analisys and things like these. But, if the orbital parameters are influenced by the charge, then by ignoring it we get a false value for the density, leading us to believe that the comet is 'fluffy'.

One more thing about measuring the density with two different methods: Of course, when you know the result you can 'adapt' your calculations to get this result (I have unfortunately some experiences in this respect), by making the right assumptions; this way you can make the second, third etc. calculation easily.

[solrey]

Regardless of Reality Check's original intentions and dishonesty, discussions of comets are just too interesting for me to stay away.

As we have said, the calculated density of comets obtained from spectral analysis of radiation, is dubious at best.
The electro-magnetic forces are relatively stronger than gravity, on long and short period comets at least. It's EM forces that dominate their motions. This means gravity based density calculations are erroneous as well.

As I've said before, density is irrelevant to the electric comet...technically.

Realistically, long and short period comets are likely at least as dense as quartz at ~ 2.6 g/cm3.
That seems to agree with:

1. The average density of the materials found according to the spectral analysis is on earth about 2.5

Not that I agree with the methodology of determining density by spectral analysis alone. Until we put a lander on the surface and poke at it, we don't really know what the densities of comets are.

According to the particles collected in the Stardust mission, at least the comet Wild-2 appears to be igneous, a crystal lattice composed of silicates and other minerals, and metals, which makes for an excellent charge carrier/natural capacitor.

Perhaps some of the differences in composition between long and short period comets, compared to main belt comets and asteroids, is in their crystal lattice structure and percentage of silicates. Of course origin would be a factor also. Given that some or most of the gas giants are captured dwarf stars, according to EU, then those long and short period comets were likely ejected material from discharge events as the dwarf star/gas giant crossed the heliopause, the material being compressed and fused in the heat of a discharge column, and accelerated into space where the material condensed and cooled. They may even be like geodes ( a certain % hollow ), or "thundereggs" ( like geodes, but not hollow ). Maybe the comets that have exploded did so because they were hollow. They say that some of the material collected from Wild-2 was created by/exposed to tremendous heat and some of the material was allegedly produced by stars. Ejection from a dwarf star would pretty much fit.

Water is a common by-product of a number of chemical reactions. The miniscule, thin layers of ice detected on some comets so far would be from those reactions. The gases coming from comets, like OH, are also the result of electro-chemical reaction chains. EDM, along with chemical reactions, causes material to flake and chip off while eroding and etching the surface.

[mharratsc]

Mike G. quoted me, then said:

mharratsc wrote:
They ARE just rocks in space.

Wish they'd put a lander 'feet on the ground' on a comet and settle the issue once and for all... Assuming it survives the debris / coma / ion tail intact and functional. But as you say, hard to get missions funded to research non-mainstream ideas.

Don't forget about the charge equalization event that would occur as it did with the impactor on Temple 1... just as Wal Thornhill predicted. Somewhere along the lines, a theory is supposed to be able to make verifiable predictions, isn't that correct? So far, the predictions made by the Standard Theory are being shot down, and all they have to sustain it are their 'confirmatory mathematical formulas'. *snort*

Back to all this though- me being one of the most lay (layest? Super-lay-tive?) laymen here *flex*, I would like to show everyone how I arrived at MY conclusion of why comets are rocks.

I arrived at my determination by taking the following Personality Self-Assessment Quiz:

This is a picture of a comet:




Now decide which of the following images YOU think it most looks like!


A. Asteroid



2. Dirty snowball



3. Fluffball



Answers:

If you answered 'A', then you are:

An Electric Universe proponent!

You feel that observation comes first! You are not predilected to choosing answers with numerical values just because. Scientific Method appeals to your innermost soul. You like ducks...

If you answered 2 or 3:

You are a Standard Model proponent!

You feel that mathematics make the world go around! You are probably a theoretical mathematician, astronomer, or astrophysicist looking for employment in the mainstream. You find that you will choose numerical answers over alphabetical ones even if they are pictures of snowballs or little baby chicks... You can't remember what sound a duck makes.

You see... I answered A!!


Prof. Donald. E. Scott wrote:

Also, there is the old saying: ―If it walks like a duck, and quacks like a duck…….‖

Quack!


Mike H.

[bboyer]

3. Fluffball

Damn! <finger-snap> I went for the electrostatic fluffball model.

[davesmith_au]

Arc-us had you said "finger-click", I would have visualized the usual "cool" type thing. But when I read "finger-snap" I started wondering what the M had to do with things ... and why only a finger...

Jokes aside, another HUGE problem with the porous low-density dirty snowball, JUST HOW DID IT GET SO POROUS? What on Earth, or out in the *cough* Oort cloud, could possibly account for a snowy dirtball being so loosely packed anyhow? If they were formed via accretion, what stopped them from becoming bigger bodies than they did? There's supposed to be enough of them in the oort cloud to sink a battleship, why didn't they all gravitate together and squash the porosity out of the snow?...

[bboyer]

Arc-us had you said "finger-click", I would have visualized the usual "cool" type thing. But when I read "finger-snap" I started wondering what the M had to do with things ... and why only a finger...

Well, shoot!

[Reality Check]

Besides which, you can talk about "measured quantities" all you want, but that doesn't make the inferrences, assumptions and estimates any more reliable. You seem to have a fixation on "quantifying" yet little in that paper is quantified in the true sense of the word.

The paper is all about quantified results.

Replace the mechanical production of jets with an electrical production of jets and you get exactly the same result – jets of gas producing non-gravitational forces.

No, replace mechanical production of jets (from within the comet) with electric discharge machining of the surface, and you get very different results. Or to put it in more human terms, exfoliation (however achieved) is not the same as farting .

Nice joke. But here is some simple physics:
Jets produced from sublimation of gas produce the same force as jets produced by discharge machining of the surface!
Look up Newton’s laws some time.

Nowhere in the mainstream literature is there any description of how the nozzle is formed to create such magical jets. And I would argue such a nozzle would likely crumble in next to no time if it was made from such a porous rock as is suggested. Not only that, nowhere is it adequately explained how same jets can form out past Jupiter, where sublimation of ice into vapour via the Sun's warmth is quite impossible.

Obviously you do not read much mainstream literature. A quick Google gives
http://cometography.com/educate/comintro.html

The black crust of the nucleus helps the comet absorb heat, which in turn causes some of the ices under the crust to turn to a gas. With pressure now building beneath the crust, the serene, but frozen landscape begins to bulge in places. Eventually the weakest areas of the crust shatter from the pressure beneath, and the gas shoots outward like a geyser and is referred to by astronomers as a jet. Any dust that had been mixed in with the gas is thrown out as well. As more and more jets appear, a tenuous gas and dust shell forms around the nucleus and this is called the coma.

IMO The”nozzle” is formed by the jet removing material from the surface of the break so that a pit forms.

You do not need much heat to sublimate frozen gases such as carbon monoxide, carbon dioxide, methane and ammonia (as well as water ice) so jets appear when comets are out past Jupiter. In fact CO jets have been observed as far out as 72 AU.

And also, how can a comet of such low density and small volume have enough gravity to hold on to such a large coma as did 17P Holmes recently? It was larger than the Sun for goodness sake, so please explain this with your numbers.

Cheers, Dave.

The coma is not “held” by a comet. It is continuously created by the creation of gas from the nucleus (see for example the EC theory). It then spreads out because the atoms have a slightly different velocity than the nucleus.

Cheers Reality

[Reality Check]

The Swift observatory measured the spectrum of the ejected material and thus the amount of water. I do not know what observed the dust (the Science article is not accessible).

Once again, IF the matter whose spectrum is measured is removed by EDM (like EU say it does) then it IS no water that is ejected, so the calculations based on the amount of water are false/ irrelevant.

The SWIFT observatory measured the spectrum of the ejected material. There was no EDM observed (this is rather obvious in the X-ray spectrum because of EMD emits X-rays in narrow bands).

I put 'observations' in quotes because there were no direct observations on the density of the comet, only calculations using the orbital parameters, spectrum analisys and things like these. But, if the orbital parameters are influenced by the charge, then by ignoring it we get a false value for the density, leading us to believe that the comet is 'fluffy'.

One more thing about measuring the density with two different methods: Of course, when you know the result you can 'adapt' your calculations to get this result (I have unfortunately some experiences in this respect), by making the right assumptions; this way you can make the second, third etc. calculation easily.

For Tempel 1 the density has been measure in 3 different ways.
Are you claiming that all quantities that have been measured in multiple ways are wrong, e.g. the mass of the electron?
Otherwise you need to support your claim that the authors of the paper falsified their results by incorporating the earlier results and that all their reviewers missed this somehow.

[Reality Check]

As I've said before, density is irrelevant to the electric comet...technically.

Realistically, long and short period comets are likely at least as dense as quartz at ~ 2.6 g/cm3.
That seems to agree with:

1. The average density of the materials found according to the spectral analysis is on earth about 2.5

Not that I agree with the methodology of determining density by spectral analysis alone. Until we put a lander on the surface and poke at it, we don't really know what the densities of comets are.

I agree - density is irrelevant to the electric comet idea because it has no prediction how dense a comet is other than (incorrectly?) labelling them as rocks and comparing them to asteroids.

Density of comets is never determined by spectral analysis.

According to the particles collected in the Stardust mission, at least the comet Wild-2 appears to be igneous, a crystal lattice composed of silicates and other minerals, and metals, which makes for an excellent charge carrier/natural capacitor.

To be more exact, the dust in the coma of Wild-2 collected by Stardust is described as below.
(http://en.wikipedia.org/wiki/Comet_Wild_2)

So far,[8] the composition of the dust has contained a wide range of organic compounds, including two that contain biologically usable nitrogen. Indigenous aliphatic hydrocarbons were found with longer chain lengths than those observed in the diffuse interstellar medium. No hydrous silicates or carbonate minerals were detected, which suggests a lack of aqueous processing of Wild 2 dust. Very few pure carbon (CHON) particles were found in the samples returned. A substantial amount of crystalline silicates such as olivine, anorthite and diopside were found,[9] materials only formed at high temperature. This is consistent with previous observations of crystalline silicates both in cometary tails and in circumstellar disks at large distances from the star. Possible explanations for this high temperature material at large distances from Sun were summarised before the Stardust sample return mission by van Boekel et al.:[10]

This may or may not make “for an excellent charge carrier/natural capacitor”.

[Reality Check]

Mike G. quoted me, then said:

mharratsc wrote:
They ARE just rocks in space.

Wish they'd put a lander 'feet on the ground' on a comet and settle the issue once and for all... Assuming it survives the debris / coma / ion tail intact and functional. But as you say, hard to get missions funded to research non-mainstream ideas.

Don't forget about the charge equalization event that would occur as it did with the impactor on Temple 1... just as Wal Thornhill predicted. Somewhere along the lines, a theory is supposed to be able to make verifiable predictions, isn't that correct? So far, the predictions made by the Standard Theory are being shot down, and all they have to sustain it are their 'confirmatory mathematical formulas'. *snort*

Do you mean the prediction from as Wal Thornhill that there would be a flash before the impact and another after the impact?
This prediction failed. There was a small flash on or under the surface and another larger flash from further under the surface.

http://solarsystem.nasa.gov/deepimpact/ ... vating.cfm

As the impactor entered the nucleus, or shortly thereafter, a brilliant flash, lasting less than two tenths of a second, appeared probably as the impactor and part of Tempel 1 vaporized. The first flash was followed by a second presumably originating deeper within the comet. The second flash was brighter still and it momentarily saturated some pixels in the instruments on the flyby spacecraft.

Actually what astronomers have is their observations and the match of these observations with the predictions of their theories. What makes this science is that as better observations are obtained the theories are adjusted (and even thrown away) to fit the data (not the other way around).

[…snipped pretty pictures look alike thing…]
Mike H.

I’m hoping that this is a joke!

[Noli Me Tangere]

Do you mean the prediction from as Wal Thornhill that there would be a flash before the impact and another after the impact?
This prediction failed. There was a small flash on or under the surface and another larger flash from further under the surface.

OK; so let's see: As reported at http://www.wired.com/science/space/news/2005/08/68258 the EU team made the prediction of two flashes. They happened exactly like they were predicted (I mean, the observational part, not the interpretation).

As the impactor entered the nucleus, or shortly thereafter, a brilliant flash, lasting less than two tenths of a second, appeared probably as the impactor and part of Tempel 1 vaporized. The first flash was followed by a second presumably originating deeper within the comet. The second flash was brighter still and it momentarily saturated some pixels in the instruments on the flyby spacecraft.

Actually what astronomers have is their observations and the match of these observations with the predictions of their theories. What makes this science is that as better observations are obtained the theories are adjusted (and even thrown away) to fit the data (not the other way around).

How can you be so sure that the first flash happened as the impactor entered the nucleus? It seems like you are more certain than the writers of the article, who use 'probably'. Actually, I catch myself noticing in various science articles how the interpretations are sold as hard facts.

About the second flash: If I understand correctly, the impactor vaporized, but somehow managed to get deep into the comet (the vapors of it?). Or it didn't get deep into the comet, but for some unknown reason a second flash followed deep within the comet, bright enough to saturate some pixels on the flyby spacecraft (why am I reminded of the Io 'volcanoes'?). If the flash happend deep within the comet, then it should't have been visible. If it was visible, then it was at the surface, even if that means that the material above the explosion was swept away. But then, how do they know that the explosion (actually flash) happened deep within? By what mechanism did the impactor 'influence' the flash deep within? After all, it was vaporized.
Please tell me if there is something wrong with my logic, maybe I can't see some possibilities. Or do I nitpick the things?

About the matching of the observations with the predictions of the theories: Well, as far as I can tell, the EU predictions matched the observations; in the mainstream articles I have only seen after the fact explanations, like the one you just presented.

[solrey]

For some reason I'm remembering an old Billy Preston tune, Will It Go Round In Circles.

RealityCheck
Jets produced from sublimation of gas produce the same force as jets produced by discharge machining of the surface!
Look up Newton’s laws some time.

Incorrect!
Electric discharge does not produce the same kind of "jet" as internal pressure forcing it's way through an orifice. Not even close. The material is eroded from the surface, is accelerated by the electric field in filaments constricted by the magnetic field.
Look up Maxwell's laws some time.

RealityCheck
The coma is not “held” by a comet. It is continuously created by the creation of gas from the nucleus (see for example the EC theory). It then spreads out because the atoms have a slightly different velocity than the nucleus.

An object with a surface area of just a few hundred kilometers offgassing enough to sometimes producing a coma as big as the Sun...or even Jupiter? Ridiculous. If comets are allegedly low mass fluffy dirty snowballs with like 75% empty space, where does all that material come from to sustain a coma of that volume?

RealityCheck
The SWIFT observatory measured the spectrum of the ejected material. There was no EDM observed (this is rather obvious in the X-ray spectrum because of EMD emits X-rays in narrow bands).

When we say EDM, it's an easier way of saying "surface erosion of an electrode", it doesn't necessarily mean arc discharge, as in lightning.
There are three modes of electric discharge:
Non-luminous
Glow
Arc
Primarily what we see on comets is both non-luminous and/or glow discharge.
The MESSENGER probe orbiting Mercury detected chemical sputtering all over the surface and as an added bonus, happened to fly through a "magnetic tornado" ripping ions from the surface. There was no x-ray signature indicating arc discharge, yet material from the surface was being liberated by electro-chemical reactions, very similar to what's happening on a comet. The electric field on a comet initiates/enhances chemical reactions that in turn enhance the conductivity and E-field in a positive feedback mechanism. A description of the circuit is the Sun as anode, the Comet as cathode and the solar plasma stream is a cation electrolyte (H+ and H2+).
It's a lot like a battery going through charge and discharge cycles. In the outer reaches of the solar system, they recharge, as they approach the Sun they begin to discharge. IMO, they are analogous to the new capacitor batteries that are being developed.

RealityCheck
For Tempel 1 the density has been measure in 3 different ways.

Our contention is that those methodologies are seriously flawed, indirect, and based on what EU contends are incorrect assumptions to begin with. Again, until we put a lander on the surface and "poke it with a stick", we really don't know for sure what the density is.

The two flashes from the Tempel-1 impactor were predicted by Thornhill because that's what is expected to occur on an electrically charged comet. How does an impactor produce two flashes, especially the second explosive flash, and get vaporized if the impactor is just hitting what amounts to a fluffy snow bank? Ballistically, it makes no sense. This is another case of mainstream scientists trying to smash "round" observations into a "square" theory.

[mharratsc]

RealityCheck stated:

Do you mean the prediction from as Wal Thornhill that there would be a flash before the impact and another after the impact?
This prediction failed. There was a small flash on or under the surface and another larger flash from further under the surface.

Don't you mean probably, or presumably failed?

http://solarsystem.nasa.gov/deepimpact/ ... vating.cfm
As the impactor entered the nucleus, or shortly thereafter, a brilliant flash, lasting less than two tenths of a second, appeared probably as the impactor and part of Tempel 1 vaporized. The first flash was followed by a second presumably originating deeper within the comet. The second flash was brighter still and it momentarily saturated some pixels in the instruments on the flyby spacecraft.

"As the impactor entered the nucleus, or shortly thereafter" ... we're not quite sure when... "probably as the impactor and part of Tempel 1 vaporized"... not quite sure what... "The first flash was followed by a second presumably originating deeper within the comet." ... not quite sure where...

RealityCheck stated:

"This prediction failed. There was a small flash on or under the surface and another larger flash from further under the surface.

Now when I compare your statement, sir, to that of the author of the quote- I find you to be guilty of stating second-hand observation as fact.

RC, you boldly stated:

"This prediction failed."

From my perspective, I don't think there's a shred of evidence to invalidate it. I don't think there is any evidence for the EU prediction that the first flash occurred above the surface, either. The evidence is not clear either way.

However, here's some things that I personally took away from my time of watching all this unfold:

Wal Thornhill said there would be two flashes... and there were.

He said that the flashes would be more energetic than were predicted by the mainstream... and they were.

He said that the craft would experience anomalies on it's approach... and it did. (NASA stated that "One was that about 20 seconds before impact, the impactor collided with a dust particle" and that "the optical quality of the last image of the impact point was degraded indicating that dust had abraded the lens of the Impactor Targeting Sensor", while Thornhill suggested that it would be caused by charge equalization. I'm amazed that NASA had the ability to see that dust particle strike that impactor at that speed... gotta give em credit for that feat. They never do really state how they came to that conclusion, do they? Seems more implied than anything)

Speaking of high temperatures... you know that article you linked, RC? That thing really did your argument way more harm than good. I remember following the predictions of what they'd find on comets (at least the ones made to mainstream media), about water ice, jets, the temperature of the thing, and etc.

This article says that the Sunward side of this comet is over 300 Kelvin! That's like 75 Fahrenheit, right? The article also said:

The coldest temperature is important because the temperature at which ices such as water, carbon dioxide and carbon monoxide turn directly into gas is below 200 degrees Kelvin.

(Ok, carbon monoxide and dioxide I'll buy... but water?? Where's the editor?!)
So they think the jets on this comet are from frozen CO1 or CO2, right? But there isn't that much of it there, because there's so much mineral content in the comet. The ice shouldn't be thick enough to keep it's temperature for long. So at room temperature, you should see the CO ice boiling off that comet! Not in it's coma or tail and don't quote spectographic whatzits at me- where are the dry ice clouds spewing off the surface like you would see with a chunk of dry ice in a bucket? Don't tell me it 'blows away', because the current hypothesis is that the coma is held intact around the nucleus by gravity, as weak as the gravity is from that body. If any ice were sublimating on the surface, you'd see fog being produced.

Observation. Occam's Razor. Logic. Simplicity.

RealityCheck, I got no beef with you. Not personally. But I'm a simple layman (with some brains in my head) that has never gotten over his love of Space from when he was a kid. I'm in my 40's now, and I have been watching all the goings-on of NASA since the last Apollo missions. I've watched predictions be made over and over, and they always seem to be followed by "but we were <suprised/astounded/shocked> by the <unanticipated/unexpected/unforseen> results".

It's gotten old. :\

I stumble along and discover these Thunderbolts and Electric Universe guys, and they seem to have an idea that shines lights into all these other dark places. I think to myself "Cool! Now NASA can get a move-on with figuring out that stuff that was baffling them!" ... but I think you know how the information was received, don't you?

RC, you came in here looking for 'mathematical proof' of the EU hypothesis, and found none. I suspect that you knew you would find none from the beginning. You denigrated the empirical approach almost immediately, by calling it observational as though that were derogatory. It almost sounds to me like you're more interested in proving that your beliefs and understanding are right than you are in actually understanding more or growing Science in any way.

I think that's sad. And I think that those responsible for educating the new kids in Academia and forcing this sort of unscientific bias down their throats should be canned and shipped off to Antartica to monitor those 'gravity wave' sensors that will never detect a damn thing.

Physics are physics. Plasma happens. Astronomy and Astrophysics cannot just 'pick the parts they like' and disregard the rest of it. Solar wind is a positively-charged plasma, that means electrons must stream back to the Sun from the portions of the Solar environment to which the positive ions are streaming to. If the comet is coming from that environment, then it will be negatively charged as well. Simple physics. The charge differential will cause EDM, and is the only logical way a comet could have a coma larger than the Sun! Comets glow in x-rays, and to think you can tell a bunch of IEEE engineers "it's the wrong spectrum of x-rays for EDM" as a dodge is the height of hubris. NASA was stunned to see a comet emitting x-rays like an x-ray star

If the Cosmological community at large and in control in the mainstream were truly interested in the science of things, I think we'd see a lot more leniency towards the Plasma Cosmology group. They're not cranks, nor crackpots. They're guys who experiment with fundamental states of matter and energy, and release raw energy in a labratory (albeit for billionths of a second) on a scale that only a star can match! You think they have nothing constructive to add?? You come here thinking you will just put these engineers and physicists 'in their places' with your interpretations of these observations?

NASA should be working with these guys, instead of with those 'theoretical mathematicians' attempting to explain the Universe with hypothetical matter and energy, and 'string theories' and all that crap.

The thing that made me cross the line into the EU camp was- whereas NASA wants me to believe a theory based upon a some computer model of the mathematical conjecture that they think best explains their observations, the IEEE guys try look at the observations from space and say "that behavior is identical to the behavior of plasma we have studied in the laboratory under XXX conditions"... what sounds more reputable to you??

Well anyway, think what you want. Like I said- I have problems with the current paradigm in Cosmology, not with you personally.

You're just a product of the current paradigm.

Oh, I almost forgot about your question:

mharratsc wrote:
[…snipped pretty pictures look alike thing…]
Mike H.
I’m hoping that this is a joke!

Nope. It looks like an asteroid. No ice, all rock. Looks as solid as Mt. Everest to me. Put your calculator down and try using your eyes on it for once.


Mike H.

[davesmith_au]

<snip>

<snip>

What they said.

Cheers, Dave.

[Reality Check]

How can you be so sure that the first flash happened as the impactor entered the nucleus? It seems like you are more certain than the writers of the article, who use 'probably'. Actually, I catch myself noticing in various science articles how the interpretations are sold as hard facts.

I prefer to go with the people who know the details about the Deep Impact data, i.e. the NASA page I cited.

About the second flash: If I understand correctly, the impactor vaporized, but somehow managed to get deep into the comet (the vapors of it?). Or it didn't get deep into the comet, but for some unknown reason a second flash followed deep within the comet, bright enough to saturate some pixels on the flyby spacecraft (why am I reminded of the Io 'volcanoes'?). If the flash happend deep within the comet, then it should't have been visible. If it was visible, then it was at the surface, even if that means that the material above the explosion was swept away. But then, how do they know that the explosion (actually flash) happened deep within? By what mechanism did the impactor 'influence' the flash deep within? After all, it was vaporized.
Please tell me if there is something wrong with my logic, maybe I can't see some possibilities. Or do I nitpick the things?

I wish I knew the answers. My guess – the second flash was visible because there was nothing above it to stop it being visible, i.e. the material had been ejected.
It was definitely not on the surface. The velocity of the impactor means that it penetrated the surface. The second flash started 186 ms after the first.

There are more details in the “Photometric Evolution of the Deep Impact Flash” paper (http://adsabs.harvard.edu/abs/2006LPI....37.2192E).

But the vagueness of Wal Thornhill’s prediction allows a lot of leeway. After all “shortly before impact” could be 1 millisecond before impact. That would be indistinguishable from an impact on the surface since the time resolution of the camera taking the images was 62 ms.