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Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

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Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#231

Post by hn_throwaway_99 »

velox_io wrote: post #226
yxhuvud wrote: post #167

Earlier quoted context omitted.

Roughly twice the amount exploded compared to Tianjin, actually. 2750 tonnes of ammonium nitrate compared to 800 tonnes of ammonium nitrates and 600 tonnes of potassium nitrate in Tianjin. So yes, quite ridiculous.

What strikes me as odd (aside from the massive shockwave), is how there were no fireballs, all other fertilizer fires have bright explosions. It's burnt rather than detonated. Here, all of the fertilizer ignited faster than the speed of sound (resulting in a virtually perfect spherical shockwave). Although the shockwave could have doused any flames, so that idea is plausible.. The other anomaly is the deep red smoke,…

I read a news article that said the deep red smoke is a hallmark of ammonium nitrate.

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#232

Post by mh- »

nitred wrote: post #186
supernova87a wrote: post #109

The amount of material must have been ridiculous to store in such a place. The blast is staggering in size, almost like the Tianjin explosion a few years ago. Collected videos: Angle #1 https://streamable.com/xmmoa7 Angle #2 https://streamable.com/nscx9m Angle #3 https://streamable.com/zbjj5f Angle #4 https://streamable.com/saoafz Angle #5 https://streamable.com/4ga1vb Angle #6 https://streamable.com/lmivb2 Angle #7…

In Angle #6, did that crack in the roof occur in real time due to the explosion or does it just seem that way due to low resolution of the camera? If that crack was due to the explosion, then I'm concerned for much of the infrastructure which is within a 3 KM radius around the explosion.

I believe we watched it happen in realtime. If you turn your volume up (careful, the initial blast is quite louder) you can hear [what I believe is] it cracking. Yikes.

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#233

Post by schoen »

supernova87a wrote: post #109

The amount of material must have been ridiculous to store in such a place. The blast is staggering in size, almost like the Tianjin explosion a few years ago. Collected videos: Angle #1 https://streamable.com/xmmoa7 Angle #2 https://streamable.com/nscx9m Angle #3 https://streamable.com/zbjj5f Angle #4 https://streamable.com/saoafz Angle #5 https://streamable.com/4ga1vb Angle #6 https://streamable.com/lmivb2 Angle #7…

I found angle #8 the most abjectly terrifying of these. :-(

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#234

Post by fanatic2pope »

fanatic2pope wrote: post #46
aaron695 wrote: post #41

I should just pre-flag this comment, so feel free. But Hezbollah use Ammonium Nitrate and could use the other small explosives stored near by. I think under current rules being actioned if there was intel people were stealing from the factory it would be considered a legitimate target. The question would be, would the analysis of intel be good enough to know exactly what was stored there and if it is clearly not an a…

> the President of the United States said it was an attack Meaningless. If Trump said the sky was blue, you'd be well advised to go outside and make sure.

Surprise! I was right.

https://www.foxnews.com/politics/defense-secretary-esper-con...

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#235

Post by Udik »

lordgrenville wrote: post #150
mhh__ wrote: post #80

Earlier quoted context omitted.

Imagine being so good that Feynman tells stories about you (rather than himself). Fermi also put Dyson down gently once "A successful theory must have either a strong physical intuition or a rigorous mathematical basis: you have neither"

Fermi was an inveterate experimentalist, always trying to measure and test things. Hence the idea of the Fermi estimate. There's a good piece about him here: https://www.lrb.co.uk/the-paper/v40/n10/steven-shapin/think-... >Fermi saw the Trinity Test as an opportunity for one of his famous exercises of rational estimation, a Fermi problem. First, he offered to take wagers from other scientists on whether the bomb woul…

> First, he offered to take wagers from other scientists on whether the bomb would ignite the atmosphere, destroying New Mexico or even the entire world.

Of course if you bet on the bomb not causing the end of the world, you can only win.

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#236

Post by [deleted] »

shadowprofile77 wrote: post #164
shadowprofile77 wrote: post #42

Nitpicking here maybe but this does not look like a 3 kiloton blast to me. Neither the size of the core explosion or the apparent shock wave damage correspond to that magnitude from a surface blast. Guessing here but I'd say closer to 2 kilotons at most. Amazingly, the massive, hollow grain silo right next to the detonation itself remained standing afterwards.

I don't understand why i'm being downvoted or why there's anything wrong with analytical speculation of this type, even about a tragedy. If anything, this very site and its comments are loaded with exactly that kind of commentary, done mostly in good spirit and tolerance for those who do it. No, i'm not an explosives expert or professional with detailed knowledge of blast yields, but like many of you, I have somethin…

[deleted]

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#237

Post by IAmGraydon »

jandrewrogers wrote: post #92
IAmGraydon wrote: post #61

Earlier quoted context omitted.

Ammonium nitrate does not release nitrogen dioxide unless it undergoes high-order detonation.

Ammonium nitrate will decompose into nitrogen dioxide under a number of conditions other than detonation. Even under detonation, it implies an excessively oxygen-rich environment.

No, it doesn’t imply an oxygen rich environment. It implies a high oxygen balance (in the explosive compound/mixture itself).

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#238

Post by KMag »

hn_throwaway_99 wrote: post #231
velox_io wrote: post #226

Earlier quoted context omitted.

What strikes me as odd (aside from the massive shockwave), is how there were no fireballs, all other fertilizer fires have bright explosions. It's burnt rather than detonated. Here, all of the fertilizer ignited faster than the speed of sound (resulting in a virtually perfect spherical shockwave). Although the shockwave could have doused any flames, so that idea is plausible.. The other anomaly is the deep red smoke,…

I read a news article that said the deep red smoke is a hallmark of ammonium nitrate.

Yes, particularly ammonium nitrate (or another nitrate) without enough fuel to consume the excessive oxygen released when the nitrate decomposes. Nitrogen dioxide is that deep red-orange. It's the most common oxidizer in hypergolic rocket motors (though, they pressurize and cool it to get it to largely dimerize dinitrogen tetroxide). The other oxides of nitrogen produced by ammonium nitrate decomposition are basically colorless. Hot nitrogen dioxide would have pretty much instantly oxidized any fuel present, releasing more energy and dramatically toning down that deep red-orange color.

This is good evidence against an intentional detonation. Even if it were arson, it probably wasn't an intentional detonation. It's inconceivable that anyone with enough research to successfully cause an ammonium nitrate detonation wouldn't have run across the fact that any of a number of cheap organic fuels increase both the power and reliability of ammonium nitrate explosions. So, it's very unlikely this was an intentional explosion, unless they were trying to make it look like an accident. If they were trying to make it look like an accident, then the objective wasn't to generate fear in the populace / political change, and any conspiracy theorist then has the problem of having to figure out what the specific target was, since we can rule out the general populace. This should put most conspiracy theories to rest, at least without silly statements by the tweeter-in-chief.

Re: Order of magnitude estimate of Beirut explosion at 3 kilotons of TNT

#240

Post by RantyDave »

yxhuvud wrote: post #168
nradov wrote: post #88

Earlier quoted context omitted.

Ammonium nitrate is essential as a fertilizer. There are no cost effective alternatives so we'll have to just accept the risk.

Well, we can still mitigate the risk quite a bit. We don't have to store 2750 tonnes of it, all in one place, for 7 years. That is asking for trouble.

We also don't have to store it next to a city.
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