I've only just noticed this article (published about a month ago) on recent research results from the "Stardust" mission obtained by scientists at the Lawrence Livermore National Laboratory (a US Govt funded laboratory). They claim, in essence, that “as a whole, the samples look more asteroidal than cometary”, that "the Stardust material resembles chondritic meteorites from the asteroid belt", and that "the dust from Wild 2 also is missing ingredients that would be expected in comet dust". Their findings were published in the 25 January 2008 issue of "Science". This is the abstract (I don't have access to the full article).

In a related article in the same issue, Richard A. Kerr writes under the title "Where Has All the Stardust Gone?" that "On page 447 of this issue of Science, researchers report that they have failed to find a single speck of the unaltered, so-called presolar material thought to abound in icy comets in the dust sample that the Stardust spacecraft returned from comet Wild 2 in January 2006."

Do these latest findings not provide further evidence that the current mainstream "dirty iceball" or "icy mudball" model of comet formation in the Kuiper belt has been falsified and that comets are simply asteroids which display cometary behaviour in certain situations?

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Where is the truth? Who sees the old hag and who the young beauty?

Technically, your two cases in your last paragraph say the same thing.

To answer your question tho: Partly yes, partly no. One thing to remember about both asteroids and comets is that we have gotten a close up look at very few of them. I think it is about a dozen asteroids and three or four comets have been imaged as anything more than a dot, and only one asteroid has gotten a truly close up study. When you add the changes in what we know about solar system development by finding extrasolar planets, it isnt really suprising that we find we dont know as much as we thought.

As a matter of fact, I would imagine that things will be in a state of flux for a while. New Horizions will give us our first good look at a KBO in a few years, and Dawn will give us our first good look at a couple large asteroids in a few years. With the nasty habit of most probes leading to more questions than answers, I think that our understanding of the solar system may change quite a bit.

When it comes down to it, I think that the lines between comet and asteroid will become a bit more blurred. Comets may end up being more icy asteroids than a different object. It may turn out that there was alot more mixing of the protosolar nebula than is currently believed. It may turn out that alot of comets were scattered out of the inner solar system by developing planets. I would think when all is said and done, you will have a range of objects from dirtballs (asteroids), to icy dirtballs (short-period comets), to dirty iceballs (long period comets/ KBOs).

Lastly remember that we still havent gotten a good look at a long term comet. All we have seen right now are short period comets. Being so close to the sun may have effects that havent been taklen into account yet.

No, technically, they are not two "case" but two "questions" and they don't "say the same thing", they are complementary: the first one questions the validity of current mainstream theory whereas the second invites support for a particular ATM theory (EU theory).

Indeed. But all the comets which have been imaged look as much like asteroids as actual asteroids do.... (including the most famous of them all, Tempel 1, of "Deep Impact" fame...) None of the alleged "comets" looks like what a comet is supposed to look like. Statistically, this is presumably quite significant: if mainstream theory were correct, we should, statistically, be imaging considerably more comets looking like "dirty snowballs" than comets looking like lumps of rock. This simply isn't the case.

If you mean that most of the extrasolar planets being found also contradict mainstream theory about solar system development (regarding their composition, size and distance from their sun), I wholeheartedly agree with you. But I reach a different conclusion: it's not that we "don't know as much as we thought" but that what we believed up to a few years ago has been shown to be wrong, precisely by the hard facts represented by the images we have obtained of comets and by the particles brought back from the Stardust mission. It's time to face up to those facts.

Why a "nasty" habit? Because the results obtained always come as a complete surprise, not to say shock?

The Stardust mission has proved that what looks like a a perfectly standard comet is in fact an asteroid. There is no reason to believe that the other comets which are to be explored will turn out to be anything other than asteroids. We simply don't need the other classes of objects you mention, except as a way of still clinging to a falsified theory.
Comet McNaught was a spectacular recent example and the latest research published here suggests, there too, that it was much more like a "dirtball" than a "dirty iceball".

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Where is the truth? Who sees the old hag and who the young beauty?

I don't see what the fuss is about. We know more about the composition of comets now than we did half a century ago when Fred Whipple popularized the term "dirty snowball". Recent findings strongly suggest the possibility that some of them originated alongside the main belt asteroids rather than out in the reputed Oort cloud. Just one more case of going back to the theoretical drawing board in response to compelling recently discovered evidence.

Comets must have a lot more icy material than asteroids, because they grow comas/tails.

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"fifty is nifty" , unknown poet

The "fuss" is about the fact that if conventional comet theory based on Fred Whipple's "dirty snowball" has indeed been falsified by recent findings (images of rocky comet cores, the latest findings of the Stardust mission, the astonishing magnitude of the Deep Impact collision, etc.) and if comets are indeed nothing more than asteroids on eccentric trajectories with regard to the sun, then the implications for the whole of cosmology are literally shattering. Quite simply, if comets are indeed no different from asteroids in their physical and chemical make-up, that means that there is no ice in or on them to sublimate under the heating action of the sun and that consequently, the jets, comas and tails they display can only be explained in terms of electrical discharge phenomena. You may think this is nothing to make a fuss about but it would prove that we do not live in an electrically neutral universe as mainstream BB theory would have us believe and that we would in fact need to rethink the whole of cosmology. Hence, by the way, the energy which mainstream defenders put into their attempts to contest, refute or deny the accumulating evidence for the asteroidal nature of comets and its implications.

Going back to the theoretical drawing board just to try to give one more little tweak to conventional theory in the hope of patching it up yet again for a few more months or years won't do. What is needed is the recognition that we live in a completely different universe from the one described by mainstream BB theory and investment in research to better understand the overwhelmingly electrical nature of it.

A thorough analysis of the electrical nature of cometary behaviour can be found in the wealth of articles on comets to be found on the Electric Universe website here.

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Where is the truth? Who sees the old hag and who the young beauty?

Your reasoning is based on the long-held but mistaken belief that cometary comas and tails are necessarily composed of water produced by sublimating ice. The belief originated in the visual aspect of comets as seen from the Earth. It was a perfectly respectable belief half a century ago when Fred Whipple coined the term "dirty snowball" because observation possibilities were limited to ground-based telescopes. The most recent observations and findings, obtained thanks to infinitely more sophisticated means and methods, have now falsified the theory. The corresponding evidence can be found here, here, here, here, here and here.

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Where is the truth? Who sees the old hag and who the young beauty?

That's a bit of an over-simplification ... 'comets', by definition, have tails, comas, etc, at least part of the time.

One conclusion from the recent results is that the centuries-old classifications almost certainly need revising.Comets to the whole of cosmology eh? That's quite a bold assertion.
(my emphasis added)

Is this the ATM idea you intend to present?

In any case, would you mind presenting the logic in a little more detail?

Specifically, how were you able to rule out every other possible explanation (than "electrical discharge phenomena")? Including all the possible explanations that have not yet been invented?
Please provide evidence for the assertion that "the energy which mainstream defenders put into their attempts to contest, refute or deny the accumulating evidence for the asteroidal nature of comets and its implications" is a direct result of a fear (?) that "we [...] need to rethink the whole of cosmology".
Please present an outline of what (alternative) research you feel should be undertaken.

Please limit your outline to only those things which you are prepared to address challenges to, and to answer questions on.
Are you intending to present, and defend, these ideas?

If so, what do you consider to be new, that has not already been presented in several other BAUT ATM threads?

ummm. No.

None of that even comes close to being scientific evidence. None of it is even close to proof.

Do you have the mathmatical background to actually defend electric comets, or am I just wasting my time here?

One very ATM idea, as something yet to be invented, is that comets ala asteroids (with very eccentric orbits) are ‘dust collectors’ in the outer regions of our solar system, Kuiper Belt to Oort Cloud regions, which gather up material thrown off from the Sun’s solar wind. This could explain, with or without ‘electrical phenomena’, why the material thrown off by comet comas is not predominantly water trails but show evidence of materials formed inside the Sun. However, and this would be truly ATM, it would necessitate a mechanism why such materials compact onto a comet very far from the Sun, while releasing or decompacting such material closer into the Sun. Solar heating may not be enough, especially since such comet tails show up already as far as Jupiter, which is far out there at 5 AU in a still cold region of space. Now the really really ATM explanation, as a hypothesis unsupported by any presently acceptable mainstream cosmology, would be if gravity (ala Toivo Jaakkola, Brans-Dicke, Pioneer Anomaly gang, et al, even Milgrom's MOND) is NOT a universal constant as now believed, but for reasons we do not yet understand it grows in its Newton G density with greater distance from the Sun.

This strange hypothesis would handily explain why comets gather up dust far out there, but release it as they ‘decompact’ closer into the Sun where this G is much lower. If this were so, the explanation (perhaps in addition to the ‘electrical discharge’ idea), might handily put to bed why comets can be just like asteroids in composition but act so differently in their highly eccentric orbits (though not always) by casting off coma tails. However, before you lay into me to prove this theory and defend it energetically, I only post this here as a possible “let’s suppose” idea without further support or argument, though in the past I had devoted quite a bit of effort into explaining this (without any success whatsoever! ) on these ATM boards. So I leave it here as a “let’s suppose” idea only, without prejudice. So comets do not have to by “icy” at all, if this were found to be true, and could be entirely made up of ‘space dirt’ only.

[BTW, I did present a mini version of this idea in the “Discussion” section of Wiki page on Pioneer, as aka Ivan D. Alexander: “ANOMALOUS ACCELERATION OF PIONEERS 10 AND 11 may be modeled on a gravitational delta effect, per the Equivalence Principle” – FYI]

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Credibility is simply incredible... sometimes even to me.
disclaimer

That's not the way I read it. It has been stated often that the iceball mudball models are incorrect due to some of the detcted material being heated.

What I have grokked, from reading all these articles is that current models underestimate the mixing that occurs early in a stellar system. In other words, the asteroids/comets form where they were expected, but there is much more mixing of inner materials to the outskirts of the planetesimal forming region.

Kindly explain why.
In a court of law, "proof" is much stronger than "evidence", by the way.

Do you have the mathematical background to actually defend "dirty snowballs"?

If you are one of those mathematicians who still actually believe that the universe out there is only there to try to do its utmost to fit in with their pet theories and equations, then you are indeed wasting your time.

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Where is the truth? Who sees the old hag and who the young beauty?

We arent in a court of law, we are in a court of physics. The two terms are much more interchangable here. By proof, I mean that there is no science content in any of the pages you linked to. All it is is word salad with no math to show any meaning. Electric comets are very much a plasma effect. No math, no proof. No proof no evidence.

Yes, but this isnt my thread and this is ATM. You made the claim, you defend it.

I am one of these space physicists who actually has the knowledge to separate the wheat from the chaff. I can actually figure the effect of the IMF on a comet and vice versa. From first principles. Can you?

If you can then I ask you to do so. Heck, I will even make it easy.

If comets are an electromagnetic effect, what is the charge density and/or charge distribution on your favorite comet, or any comet for that matter?

You might want to have a read of this article, and possibly this page.

Are you really claiming that there is no ice on or in them?

dont know...but here comes a crazy idea....

it woudnt be that comets are "younger" asteroids?, we have seen that in the asteroid belt there are some rocks with ice and dust on its surface, so i think these objects would have the same behavior of a comet near the sun...so it might be that the ice and crap over the rock get wasted after some rounds traveling near the sun...

any suggestion??

I don't think anyone correctly predicted what would happen when Deep Impact struck Tempel 1. I'm not sure anyone knows even now! We do know there was ice, but ice represented a small percent of the dust. There were also clays - not expected to exist in Kuiper belt objects. We don't know if the few comets we have observed are oddballs, or