Video taken after the 9/11 attacks on the World Trade Center towers in New York show there was a hot yellow stream of fluid material pouring down the side of the WTC2.

According to FAQ about the NIST investigation:

Pure liquid aluminum would be expected to appear silvery. However, the molten metal was very likely mixed with large amounts of hot, partially burned, solid organic materials (e.g., furniture, carpets, partitions and computers) which can display an orange glow, much like logs burning in a fireplace. The apparent color also would have been affected by slag formation on the surface.

Dr Steven E. Jones conducted an experiment to try to replicate this, but failed:

I decided to do an experiment to find out. Our group melted aluminum in a steel pan using an oxy-acetylene torch. Then we added plastic shavings -- which immediately burned with a dark smoke, as the plastic floated on top of the hot molten aluminum. Next, we added wood chips (pine, oak and compressed fiber board chips) to the liquid aluminum. Again, we had fire and smoke, and again, the hydrocarbons floated on top as they burned. We poured out the aluminum and all three of us observed that it appeared silvery, not orange! We took photos and videos, so we will have the recorded evidence as these are processed. Of course, we saw a few burning embers, but this did not alter the silvery appearance of the flowing, falling aluminum.

We decided to repeat the experiment, with the same aluminum re-melted. This time when we added fresh wood chips to the hot molten aluminum, we poured the aluminum-wood concoction out while the fire was still burning. And as before, the wood floated on top of the liquid aluminum. While we could see embers of burning wood, we observed the bulk of the flowing aluminum to be silvery as always, as it falls through the air.

This is a key to understanding why the aluminum does not "glow orange" due to partially burned organics "mixed" in (per NIST theory) - because they do NOT mix in!

Have anyone else tried the same experiment with different results? Have proponents of the official narrative or the debunkers tried this?

  • 6
    Keep in mind that almost every metal out there glows colors that range in a broad spectrum of oranges to whites if you heat them enough. You can find online a lot of people doing things with both orange-glowing molten aluminium and silvery liquid aluminium - the difference being only the metal's temperature.
    – T. Sar
    Jun 7, 2019 at 17:54
  • someone edited the question, I especially asked for other experiments. Internet is full of arguments, but I would prefer to see a visual evidence. Impossible to ask here anything without someone changing the question. Why don't create your own question?
    – gavriel
    Jun 7, 2019 at 17:58
  • @T. Sar have anyone attempted to determine the temperature from the color?
    – gavriel
    Jun 7, 2019 at 18:00
  • Sorry to revive this old thread, but is there an indication of why they conlcuded it must be molten metal, and could not be, say, burning fat/wax? The video is too low resolution for me to be clear on that.
    – bukwyrm
    Nov 11, 2021 at 10:55

3 Answers 3


Very probably, yes. The thing is, the NIST report does not claim, absolutely definitively, what it is, because no one took sample of the stream of metal at the time if was flowing. They "conclude" that it probably was, because it's a logical explanation of the observed metallic flow.

Lacking a direct sample as evidence, they could only speculate and give likely or probable explanations for observations that were made.

Keep in mind, this is only relevant to people like Jones because they are making the wildly improbable claim that it was molten structural steel, instead of aluminum. By claiming it is not aluminum that was observed, they still don't have an explanation of how steel would melt to the point of pooling and running down the exterior, but doing so without the much lower melting point aluminum melting and being observed to melt, despite the abundance of that material along the exterior areas of the structure, and from the plane, itself.

(From the same link in the question) -

NIST reported (NIST NCSTAR 1-5A) that just before 9:52 a.m., a bright spot appeared at the top of a window on the 80th floor of WTC 2, four windows removed from the east edge on the north face, followed by the flow of a glowing liquid. This flow lasted approximately four seconds before subsiding. Many such liquid flows were observed from near this location in the seven minutes leading up to the collapse of this tower. There is no evidence of similar molten liquid pouring out from another location in WTC 2 or from anywhere within WTC 1.

Photographs, as well as NIST simulations of the aircraft impact, show large piles of debris in the 80th and 81st floors of WTC 2 near the site where the glowing liquid eventually appeared. Much of this debris came from the aircraft itself and from the office furnishings that the aircraft pushed forward as it tunneled to this far end of the building. Large fires developed on these piles shortly after the aircraft impact and continued to burn in the area until the tower collapsed.

NIST concluded that the source of the molten material was aluminum alloys from the aircraft, since these are known to melt between 475 degrees Celsius (900 degrees Fahrenheit) and 640 degrees Celsius (1,200 degrees Fahrenheit)—depending on the particular alloy—well below the expected temperatures (about 1,000 degrees Celsius or 1,800 degrees Fahrenheit) in the vicinity of the fires. Aluminum is not expected to ignite at normal fire temperatures and there is no visual indication that the material flowing from the tower was burning.

So the NIST looks at this observation, with the claim that it was nefarious because an office fire would be able to melt steel, and points out that was a ready and expected source of aluminum for the office fires to melt at the observed temperatures. No magical explanations needed.

As far as Steven Jones not being able to replicate an ignited skyscraper melting an airplane with some aluminum, a skillet, a propane torch and some wood chips to throw into it...... that's more than a bit bizarre to think that's any kind of debunking. Interesting that he didn't try adding plastic and/or glass, which would actually melt under heat. Perhaps he wasn't all that interested in seeing whether the theory could be confirmed.

The idea that molten aluminum would only appear to be silver is utter nonsense, without any kind of evidence to back it up. This seems to be common knowledge among anyone who has dealt with metals.

Name: Bob Status: student Grade: 9-12 Location: MS Country: USA Date: Fall 2010

Question: What color will any metal be (zinc, for example) radiate when it is heated to its melting point?

REPLIES: Molten metals usually seem to have simple thermal-glow colors. Oxide crystals, glass, metal salts, and organic chemicals show much more variety and color-saturation.

Most liquid (melted) metals are silvery, which is high reflectivity and low emissivity, so they try not to radiate much of any color. But, usually the reflectivity is less than 90%, so the emissivity is >10%, so some glowing will happen. Impurities on the surface, such as oxidation or slag or carbon, by being dark instead of silvery, could enable additional radiation. And if the impurity added a color of its own, the glowing could pick up some color bias.

The metal can only glow in the visible range if it is hot enough for a black body to glow red, orange, yellow, white, or hotter. Look up black-body radiation and color temperature. Molten Aluminum at 660degC, for example, is just barely hot enough to glow deep dull red in a dark room.

...... Your question does not have a simple answer because there is no single answer. Here is a (short) list of factors involved: 1. The temperature. Any object, regardless of and independent of its composition will have a "color" from dull red to blue-white that depends only its temperature. If you want to track this source down search the internet for "black body radiation" and look at the X-axis scaled in wavelength between 400 (blue) to 700 (red) nanometers, which is the wavelength range of visible light. Also you can see the "red" end by looking at the burners on an electric stove. 2. The color also depends upon reactions with atmospheric gases, especially oxygen and nitrogen, which are the major components of air. The oxides and / or nitrides that form are usually less dense than the metal and tend to float to the surface. Oxides and nitrides tend to be white to gray, but this is also piled on top of the black body radiation, and some oxides--iron for example, may be red to black, depending upon which oxide is present. These colors apply at room temperature. What happens at the melting point of iron is difficult to say. 3. Sodium is an impurity that is difficult to exclude, since it is a component in many materials, e.g. glass to mention just one. Sodium has intense yellow emissions at 569 & 590 nanometers (called the sodium D-lines). These can obscure any other visible emissions by other metals. Of course the presence of carbon can give the characteristic orange of a carbon flame.

As I said this is a short list. There are no doubt a number of others depending upon the metal, its purity, and the wide range of melting temperatures of metals.

Some conspiracy addicts have tried to invoke the "thermite reaction" in the 9/11 tragedy, and part of their claims has to do with the color of flames from the Twin Towers. However, those claims are not credible if the chemistry is examined carefully and impartially. They know the answer they want and will bend the data to fit their presumptions.

Department of Energy "Ask A Scientist!" Archive

  • " Interesting that he didn't try adding plastic and/or glass, which would actually melt under heat. Perhaps he wasn't all that interested in seeing whether the theory could be confirmed." - at least he tried, the debunkers from popular mechanics or metabunk did not try, while this is one of the most common question people have, seems like no one spend time to debunk it. While they spend a lot of time to debunk questions no one asked. I originally asked for videos or pictures of experiments, but someone changed my question.
    – gavriel
    Jun 7, 2019 at 19:13
  • "they still don't have an explanation of how steel would melt to the point of pooling and running down the exterior," - they assume it was a product of thermitic reaction, mostly iron. In the following paper, Jones published finding of Iron microspheres containing alumininum and sulfur. Also chips of unreacted nanothermate.
    – gavriel
    Jun 7, 2019 at 19:24
  • I have read the NIST report, in my original question, I asked for videos of experiments. But it is impossible to ask a question without someone completely changing it.
    – gavriel
    Jun 7, 2019 at 19:26
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    @gavriel - no, because they either have to completely invent a substance like "nanothermite" that does not exist, or they have to invent a method for using thermite that is either impossible or goes completely how it is used. "Microspheres" - an enormous building with steel beams collapsed under tremendous weight and speed, creating a giant choking cloud of pulverized material - of course there's going to be small bits of iron-based material - aluminum - sheathed the outside of the building and, you know, planes, suphur -gypsum/wallboard - so everything expected without thermite. Jun 7, 2019 at 20:08
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    And, no, that laughable "experiment" is not what I'd call "trying," any more than me throwing a paper airplane and declaring "yep, space travel is clearly impossible, the moon landing was a hoax" would be "trying" to replicate the Apollo missions. What you need to understand is that if the NIST did not attempt to replicate it, themselves, it's because it's already well known or demonstrated. They didn't have to melt aluminum to come up with the melting temperature, it is already well known. They didn't just make up "it will appear yellow with impurities," for no particular reason. Jun 7, 2019 at 20:10

In my opinion, this experiment is so simplistic it replicates nothing. Molten aluminum is difficult to handle and can be extremely dangerous and can even explode under certain circumstances. (See: https://www.youtube.com/watch?v=8VInPykR6WQ and P.D. Hess and K.J. Brondyke, April 1969, Metal Progress)

Aluminum explosions in well regulated industrial settings are all too common and seem to be of two types: substances with water (or water itself) coming into contact with molten aluminum, or certain reactive substances chemically combining with molten aluminum. (https://aluminiumplantsafety.blogspot.com/2020/09/casthouse-is-destroyed3-dead-4-injured.html)

Another problem with this experiment is that aluminum from the airplanes and building materials would have had available for mixing any combination of architectural materials.(Forensic Fire Scene Reconstruction, Third Edition). Concrete, glass, zinc, iron oxide, asbestos, gypsum, marble, water, copper, water from plumbing, (https://www.quora.com/What-materials-are-used-to-build-skyscrapers, Jordan Hull, et.al) could have contributed different chemicals. Of particular concern, iron oxide (likely present as rust in the Twin Towers) is one of those substances that explosively combines with molten aluminum. (P.D. Hess and K.J. Brondyke, April 1969 issue of the trade journal Metal Progress) This combination is called thermite, used to fuse metals.

Another major problem with the experiment is that Mr. Jones did not take careful notes of the reaction times. Differences in time can produce very different characteristics in metal alloys (Imperial Metallurgists, LLC, Phase Transformations in Alloys, https://www.imetllc.com/phase-transformations-in-alloys/). Given the long times and many chemicals in the furnace-like conditions, who knows what the final alloy would have been? If you cannot accurately replicate the alloy mix, offering theories about the color or composition of the molten metal is not practical or useful.

The main takeaways here are: (1) the need for precise and accurate replication of the physical environment before drawing conclusions (National Academies, Reproducibility and Replicability in Science), and (2) as the children's science trope says, "KIDS, DO NOT DO THIS AT HOME" (https://tvtropes.org/pmwiki/pmwiki.php/Main/DontTryThisAtHome). Melting aluminum and tossing materials in is not the best science, nor is it safe. The best industry safety efforts have still resulted in about 150-170 major explosions each year under the highly controlled conditions in aluminum casting plants. (The Aluminum Association, ANNUAL SUMMARY REPORT ON MOLTEN METAL INCIDENTS FOR 2019,September 2020.)


You might also consider that if molten aluminum gets hot enough it will glow. Here is an image of molten aluminum being pored into a crankcase mold. Here is another picture at a different aluminum foundry. Here is a general discussion of molten aluminum in rebuttal to Steven Jones' statements.

  • Yes, but they argue that it must be aluminum because of its low melting point. If the metal was yellow hot, it could be other metal as well then and you would have to explain the high temperature.
    – gavriel
    Jun 9, 2019 at 23:47
  • @gavriel - You're talking in circles now, which is pretty standard for conspiracy nonsense. If the metal was yellow hot, no, it could not be another metal, because the only other metals present would not be molten at those temperatures. You would not have to explain high temperatures because there were no high temperatures. Jun 10, 2019 at 14:16
  • For aluminium to glow orange, you'd need it to be 900C, melting steel is approx 1400C, so it is white hot. Cameras often depict it yellowish, but it is truly white.en.wikipedia.org/wiki/Incandescence
    – bukwyrm
    Nov 11, 2021 at 11:03

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