His objection to the thermite hypothesis was
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...The most common thermite is actually a mixture of rust and aluminum.
Uh, the rust is the oxide.
It provides the energy for burning the aluminum.
But there were no aluminum oxides in the material.
So that basically completely blows out of the water any idea that this was thermite.
You know, we're still left with a mystery.
We don't know what it is.
I am not an expert in chemistry. Any thoughts on Nolan's argument?
Don't worry, the authors of the 2022 paper weren't experts in chemistry either, and nor am I.
Edited to add: none of the "
shouting" below is aimed at you
@F.Moon or anyone else here- it's just Nolan, Vallee and co.'s dreadful 2022 paper makes me so angry...
It is clear from the results reported by Nolan, Vallee, Jiang and Lemke (2022) that their spectroscopy set-up returned results for individual
elements, not
compounds.
See "Improved instrumental techniques, including isotopic analysis, applicable to the characterization of unusual materials with potential relevance to aerospace forensics", Garry P. Nolan, Jacques F. Vallee, Sizun Jiang, Larry G. Lemke,
Progress in Aerospace Sciences Vol. 128, 1 January 2022, PDF attached.
The authors provide results for
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...the principal isotope counts for the most abundant elements between mass 20 and mass 60 for samples 1, 3, and 5 (samples 2 and 4 are not presented here due to the low ion counts). These principal elements were Na, Mg, Al, Si, Ti, Fe, and Mn.
Page 10, paragraph 2 as published [i.e. PDF below, the OP here was based on a pre-publication text draft of the same paper].
They had earlier written (page 10, 1st para.)
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The measurements for each of the ten depths for each of the grains (subsamples) 1 through 5 were summed and are shown in Fig. 7 as raw values between 20 and 60 mass units.
So, nothing with less than 20 or more than 60 units of atomic mass.
Carbon, and Oxygen, were below their detection threshold.
And they could detect elements- not compounds.
That is why there were no aluminium oxides- indeed, oxides of any sort, 44 years after the event- found in their sample.
Earlier studies (1977-1978) by Coan and Kayser appear to have had lower and higher detection ranges respectively, which must cast some doubt on Nolan, Vallee et al.'s
apparent claim (in their paper's title) of their using "
improved instrumental techniques, including isotopic analysis, applicable to the characterization of unusual materials with potential relevance to aerospace forensics"...
From the OP:
Carbon, relative atomic mass (AKA standard atomic weight) 12.011 is omitted. If the Council Bluffs material had significant steel content as the 1970's studies indicated, an estimate of carbon content might have been useful in a technology forensics context. Coan's 1977 study quantified carbon at 0.7%.
Kayser's study (1977 or '78) indicated returns for tantalum and tungsten, relative mass 180.948 and 183.84 respectively, beyond the limits of Nolan, Vallee et al.s' investigative set-up.
There is no discussion of the forensics implications of using an investigative technology apparently incapable of detecting elements/ isotopes with less than mass 20, e.g. carbon (carbon composites are increasingly used in aerospace engineering, the Airbus A350-900 XWB airframe is 52% carbon composite) or heavier than mass 60 (from an aerospace artefact, plutonium 238 might indicate a small thermoelectric generator; plutonium 239, carriage of a nuclear weapon).
The only example that the authors provide in their paper of a known aerospace artefact which likely underwent systematic forensic examination using the most sophisticated means then available is Cosmos 954 (see "8a1. Discussion of Cosmos 954", below). That craft's nuclear reactor and fuel would have been of great interest- perhaps the primary interest- to American investigators; but the techniques used by Nolan, Vallee et al. would have been of little use in this regard.
A brief summary of Coan's findings are under "4.1", page 8; a table of Kayser's findings, "Table 1", page 9.
Although Nolan, Vallee
et al.'s phrasing is ambiguous, they quote Coan's findings:
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The slag was a foam material containing metallic iron and aluminum with smaller amounts of magnesium, silicon, and titanium, "probably present as their oxides." The white ash inclusions were "principally calcium with some magnesium, again probably as oxides."
The authors provide pie-charts of their 5 subsamples, Figure 9, page 11:
(The authors have not included manganese, which they detected, in these charts, they do not state why; discussed in OP).
NB the authors believe subsamples 2 and 4, which appear to have significantly less iron, were partially oxidised and not well ionized during analysis.
So, predominantly iron, aluminium, silicon. We do not know if silicon was present in the pre-melt materials or combined from the sand/soil the burning material was on, or possibly both.
Even without knowing chemistry (my knowledge is very limited and er... rusty) the argument by Nolan that if one of the components of the most common form of thermite wasn't present, proves it wasn't thermite, is a false one, as it could have been some other formulation of thermite that was used, e.g. one which used magnesium instead of aluminium.
I think you're right, as far as I understand these things.
All of Nolan, Vallee
et al.'s 5 subsamples contain iron, and potential fuels aluminium, silicon and magnesium (if the iron was originally present as iron (III) oxide,
remembering the authors could not detect oxygen);
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Thermites have diverse compositions. Fuels include
aluminum,
magnesium,
titanium,
zinc,
silicon... Oxidizers include
bismuth(III) oxide,
boron(III) oxide,
silicon(IV) oxide,
chromium(III) oxide,
manganese(IV) oxide,
iron(III) oxide,
iron(II,III) oxide...
Wikipedia,
https://en.wikipedia.org/wiki/Thermite (Oops, nearly forgot myself, the samples also included manganese, another potential oxidizer if present initially as manganese (IV) oxide).
Nolan, Vallee
et al. don't raise the supposed lack of aluminium oxides as a reason to challenge the thermite hypothesis in their 2022 paper. Instead they found it somehow inexplicable that 15.9 to 25 kg of molten metal was still warm 2 hours later.
The material composition of the samples tested by Nolan, Vallee
et al. is entirely consistent with appropriately-chosen swarf/ fine metal scrap melted by an improvised thermite, which might have been sourced from those same materials.
The estimated maximum mass could easily be carried by a fit person on foot, in one 33.75 l (2100 cubic inch) backpack (and perhaps a much smaller one, my estimate was based on the material having 10% the density of iron).