[meteorite-list] Re: Tektites III (Short)
From: meteorites_at_space.com <meteorites_at_meteoritecentral.com>
Date: Thu Apr 22 09:43:32 2004
First off, Kelly-- the format you are used is very, very confusing-- It is hard for me to tell who is saying what, or said what.
So I will have to sort it out to make sense of it. The "a" and sequential lettering does nothing to clarify the picture, and makes debate even harder.
Webb's will be "WEBB>"
FOLLOWED BY THE ">" THE NOTATION GIVEN BY THE SERVER IN PREVOUS QUOTES.
Mine will be "SCHONER>" followed by my text without the ">" which is applied only to previous text that I am responding to.
WEBB> On Mon, 16 July 2001, Kelly Webb wrote:
> Hi, Steve and All,
> This really will be short.
> a) K. P. Florensky (1963) and I. T. Zotkin and M. A. Tsikulin (1966)
> reconstructed the airburst height of the Tunguska object as 5000 meters,
> or about 3 miles. I can't give the titles; they're in Russian. Terminal
> velocity at which cascade fragmentation and airburst occurred: about
> 3350 meters/second. Dynamic pressure: about 200 kilograms per square
> centimenter. If the whatever it was had been just a little heavier
> (denser or fatter) or could have taken a little more dynamic pressure,
> there would been one helluva hole in Siberia.
> The Russians seem to be very lucky this last century. Shikote-Alin
> broke up at the last minute, too.
SCHONER> And even Sikhote Alin, an iron, broke up in a terminal blast just before hitting the ground. Iron is much, much more solid than the comets that break up by solar wind and radiation pressure.
> b) "Comet Linear C/2000 A2... broke up under the influence of solar
> wind pressure, and as it heated up. Comet Kehotek (sp) did the same."
> The suggestion that solar wind pressure broke up these comets is unique
> to you as far as I can tell. The heating of volatiles and the resultant
> gaseous evisceration of the nucleus is the excepted explanation for the
> breakup of comets rounding the Sun. Solar wind may possibly be a cause,
> but you are introducing a new hypothesis.
SCHONER> One needed to explain in response to your skepticism about Mega Tunguska events as to a plausible reason that such events CAN occur if the conditions are right.
WEBB> quoting me an makin point)
"I DID NOT say that they are anywhere as insubstantial as you are
> claiming. You have created a "straw man" and are running with it."
> Steve misses the point entirely when he acuses me of creating a
> "straw man." My point is that airbursts are only possible when an
> impactor cannot penetrate the atmosphere to the surface of the Earth. He
> specified a 10 km impactor that airburst, a situation that could only
> happen if the impactor had a density less than the atmosphere itself, an
> impossibility in a real universe. Above a certain mass, ground impact
> must occur.
SCHONER> Prove the above statement! What facts do you have? And have you as I have challenged you to provide information as to the desiity factors that
would allow for such an event.
Clearly such an event happened as the strewnfield distribution of the Australites and the lack of a crater to explain it indicates such an event.
Just because your "equations" say that such an object can't produce such an event does not mean that what you have deduced is in fact, fact.
As I have mentioned and challenged you repeatedly before-- where is the function for structure in the equations that are based on much, much more solid objects.
We are not talking about gas balls here with less than normal atmospheric densities. We are talking about comets-- and we do not know much about their structure nor how such bodies traveling at the highest possible cosmic velocities in retrograde orbits against the Earth will behave when the strike, and I say strike the
KELLY> The point is that they would have to be that low in density to be
> that size and still airburst. The type of this argument is the "reducio
> ad absurdum" (lousy spelling) and it means if you take all his claims
> together and they imply an absurd result.
> The "math" (really arithmetic) is simple, straightforward, 8th
SCHONER> HA! Give me the equations and I will present them to an 8th grade class and see if that is true!
But irregardless of that, the FACT IS-- that something is wrong in the modeling that you are presenting for if, as the evidence presented in stretch tektites, and distribution patterns in the strewnfields indicates a huge airburst (Mega Tunguska) event-- then clearly, logically, something is not right with the
The observed facts do not support the model-- therefore the model might be faulty.
WEBB > Now, he says, "solid ice with probably trace or measurable
> quantities of dust scattered within," which would imply a density of 0.2
> to 1.2 gm/cm^2, or back to a conventional and real-world object which
> would penetrate the atmosphere and reach the surface (fail to airburst)
> at any size over 160-200 meters or so.
SCHONER> Here we go again with that faulty model.
WEBB> (quoting Schoner)
> d) "Your step-by-step density reduction argument is faulty. It has
> assumptions that do not take into account the obvious physical nature of
> comets. Nor do they take into consideration the fact an object such as
> a comet moving at hypersonic velocity will respond in the same way than
> a much more solid body such as an asteroid will respond given the same
> speed and angle of attack."
> You get so mad, Steve, that you get it turned around. My point was
> just that, that they would behave like any object of similar mass and
> velocity. I said that over and over again.
> Then, a few pages further on, I say that: "In a sufficiently
> energetic event, nothing matters but the raw parameters of energy,"
> meaning mass and velocity, and Steve hollers, "WRONG!"
> Which is it, Steve?
SCHONER> Didn't you read what I wrote? What ticks me off is when a notion that I never intended, and have repeated tried to correct is used as the coupe de grace in a "straw man argument"
That ticks me off, and I will point it out immediately focusing on the error when I see it.
Now-- in a nutshell the energy expenditure is in the bolide phase spread out over the distance of travel of the bolide-- until it comes to an abrupt stop from
hypersonic speed-- then it releases all of its remaining kinetic energy in one very abrupt blast. A terminal burst. Leonid (cometary) particles do this at
altitudes of 20 to 30 miles. In an instant they vaporize in a flash, and release all of their kinetic energy in an instant. They are acting like tiny Tunguska events. Why they do this is not known, but that they do is beyond doubt.
Now suppose that that happens with a swarm of comets (from a fragile comet that broke up like Shoemaker-Levy, or Linear, or Beila's (1882). Tell me that
such an event could not produce a swarm of Tunguska events such as Dr. John Wasson you said proposed, or at the very least one large Mega Tunguska event.
I want to remind you and everyone, that I am not the author of this idea--
I did not pull it out of thin air. Billy Glass, and quite a few others saw a potential connection between the dynamics of a Tunguska event that if carried to a much larger scale could provide a model to explain the formation as well as the strewnfield distribution of known tektites. If such is the case, as I am certain that it is, then there is something wrong with the models that you are using to dispute the Mega Tunguska theory.
> e) See RAHE, VANYSEK, & WEISSMAN, "Properties of Comet Nuclei," in
> HAZARDS DUE TO COMETS AND ASTEROIDS, pp. 597-635 on densities,
> structural strength, tidal disruption, and fragmentation of comet
> impactors. This one selection happens to discuss most of the issues
> about comets you have raised. The minimum strength of the comet body can
> be estimated from their rotation periods (too weak and they fly apart).
> They discuss the fragmentation of comets, which they attribute to
> heating, and which only occurs in 1% of short period comets and 4% of
> long period comets. The discuss how far apart the fragments of a comet
> that breaks up on the way down can fall from each other (the craters are
> so close that they overlap or are inside each other).
SCHONER> Interesting quote, Kelly. I see that fragmentation of long period comets is as I had previously stated higher than short period ones--
And by a factor of four to one, which is quite significant. Now that does not take into account the comets that broke up before they could be observed.
And I and others wonder how many long term comets don't even make it closer to the Sun than say the distance of Venus or Murcury. There are questions
in this regard.
This would indicate that there ARE structural differences between the long term and short term comets. Also the long term ones have much higher
velocities than the short term ones-- what happens when one of these fragile bodies hits the Earth's atmosphere at the fastest possible speed? It will, I think slam into the air with the same effect as if it slammed into the ocean or solid ground. In other words, it produces it crater in the air rather than on the ground or the ocean.
And suppose that the comet in question has a retrograde orbit like the on that produces the Leonids-- factor fragility of such and velocity into those
equations, and run suspected factors regarding structural strength through a supercomputer like the one that was used to model the Mega terminal Tunguska blasts on Jupiter from Shoemaker Levy. I will bet that you will come up with a much different result than the limited one that you are using to discredit the concept of Mega Tunguska blasts in the Earth's atmosphere.
We don't know enough to formulate a valid model-- If tektites were formed by in an impact event to the Earth, as I an others think the evidence indicates,
then there clearly is a problem with the model you are using..
> f) True, trinitite was not formed in the exact conditions of
> tektites, but the sand at and around the base of the blast tower was in
> physical contact with a little patch of the universe whose thermometer
> suddenly read 30,000,000 degrees that July dawn! If that won't create a
> tektite, just how energetic do we have to get? (The glasses from 15
> megaton boosted fission bombs don't look like tektites either.)
By about a thousand million times or more greater! Also, you must remember that the crater in the air with cavitation from the ground to space itself would have created very odd conditions. Conditions that would not come anywhere near the conditions of a mere 15,000 to 20,000 Kilo ton blast. So the Trinitite analogy you use falls short-- way short.
> g) Far easier to build pyramids that make tektites.
SCHONER> Not so if you ask an archeologist-- ha ha heee he.
One thing that I noticed about you, Kelly, analogies you do not like. For the most part they seem to fly right over your head. True theorists I am told like big pictures, models, ideas based upon observable facts. They then incorporate or utilize math and equations to prove, or lend support to those models.
That is the approach that should be taken here in the Tektite question.
Supposing that Mega Tunguska events COULD happen, (without saying that they do) what would the conditions be that would allow for such an event?
If after such an exercise, no realistic conditions can be found that conform with natural events or laws as they are on this world then the idea is probably
However if such conditions, based upon what we know or speculate allow for such an event and it can be proven mathematically-- then that would lend support to it.
In this regard, if I recall in "Acta" years ago a mathematician was perplexed with the story of the great Chinguetti (sp) Iron. Theorists using equations exactly like yours said that such a huge iron was impossible because its cosmic velocity would be such that it would hit the ground at cosmic speed and vaporize at any angle.
The mathematician was not convinced, and he then went about seeking information regarding conditions that would allow for such a mass to reach the ground intact.
Using as many variables of velocity, angle of attack, and air density that could be found-- he came to very remarkable conclusion-- such a huge mass *could* make it to the surface of the Earth without vaporizing if it came in at a low cosmic velocity, and at a very, very low angle of attack. Not so low as to bounce out off the Earth's atmosphere, but to penetrate it, and gradually orbit as a huge fireball expending its
energy all the time as it spiraled ever closer to the Earth's surface. Then when near to the ground it would have lost most of this cosmic velocity and then bounce off the Atlantic ocean several times, to land in the place where it was allegedly found.
His work was convincing enough to make it to "ACTA" and though it was an interesting idea it did not prove the existence of such a huge iron. But it did shed some light on the possibility, though remote, that such an event *could* in fact occur-- but only if the conditions were right.
Now apply that approach to the tektite dilemma.
They exist, and Mega Tunguska(s) events seem to be the best explanation. The models as they are and as you say do not allow for it.
I challenge those that can manipulate such models to find the conditions by which such events can, or could occur.
It will not prove that that is the way it happened, all that it will prove is that it is possible.
And I am convinced, based upon the evidence that tektites provide, that a model can be formulated that can explain them and the process that created them.
> h) "Just because a cosmic body has such and such a mass DOES NOT
> mean that when it hits our atmosphere it will also hit the ground."
> I really hate to disappoint you, Steve, but that's exactly what it
> means. Above a certain mass, it's inevitable.
SCHONER> Doubtful-- as there are as I have repeatedly said, variables in your models, and equations that do not take into account factors that we do not as yet know-- the nature of the impactor, and how such will respond to the Earth's atmosphere when it strikes it at what could be the highest cosmic speed posible. That is an icy comet from the Oort Cloud coming in on a reetrograde orbit striking the Earth's atmsophere in a head on collision.
WEBB> But look, you are not going to take my word for it; I can tell that.
> Why don't you just take the question to someone whose knowledge you
> trust and ask them?
SCHONER> Yes, I already have-- the late Dr. Shoemaker, as well as Dr. John T. Wasson, and Dr. Roddy, and others. The consensus was and is that tektites were most likely caused by impact events that are related to comets in "Tunguska" type events.
So... There you have it.
The tektites, in their silence speak for themselves.
They did not come from the Moon--- Composition, and distribution patterns on the Earth, as well as splash, layered, and especially stretch forms preclude that.
They did not come from tektite impacting bodies (tektite meteoroids)--Their composition, splash forms, layered, and stretch forms, as well as the fact that they do not fall regularly preclude that. And where is the crater?
They are found scattered over the Earth, in patterns that indicate impact-- There are layered forms, splash forms, and stretch forms that could only have been produced close to the point of origin. And in at least one tektite field, Ivory Coast, a crater is associated, but is too small to be the primary source.
Conclusion-- tektites were formed on the Earth in events of staggering magnitude, that left small or no craters, yet scattered tektites over as much as 10% of the surface of the Earth.
Mega Tunguska events involving high cosmic velocity comets are the only viable explanation.
And lastly, in this regard-- what if the tektites themselves are mostly cosmic?
That is the remaining silicate residues from the comets that created them.
We think that the solids in comets are carbonaceous, with silicates-- but what if this assumption is wrong? What if there is not as much carbonaceous material as one would think? Or what if there was
and the Mega Tunguska event not only dissociated the oxygen hydrogen bond, but latched the carbon to the free oxygen from vaporized water in that wierd environment that was the fireball that created the tektites?
Carbon dioxide would be the result, and the hydrogen would be launched out into space just as it was seen to do in the Shoemaker Levy blasts on Jupiter.
I wonder what those black circles were that I observed through my modest 4.5 inch refractor that night.
Could it have been micro-tektite dust?
It would be nice, very nice to have known.
Tektites exist. They are not from the Moon. They are not from tektite parent bodies. There are no craters of size to explain them if the impact models that we have today are true and such impactors that created them MUST strike the surface as Kelly maintains.
But do they ???
Something is wrong in the picture, and I think that it is the models Kelly uses that are in error. They do not reflect the true nature of the event, or reality..
And we won't know for sure until more information is gathered about the comets that might be the culprits, and modifying the models to include the facts.
P.S. I will be setting up a web page presenting the remarkable stretch tektite that I think offers clear and convincing evidence that tektites formed here on Planet Earth. I will post a link to it soon.
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Received on Wed 18 Jul 2001 12:36:53 AM PDT