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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

#131

Earlier quoted context omitted.

This story is on the front page of every major news site in the world right now. They're not providing an "in-depth analysis" because there aren't yet sufficient facts to analyze. Even the authorities don't yet know what actually exploded, or what caused the explosion, or the number of dead, or the number of wounded, or the number of missing. Get off your high horse.

> Get off your high horse. President Trump(And other world leaders) commented about 3 hours ago on this issue. So the fact it's now made a headline is I guess your horse not mine. And authorities do know what exploded, and have made statements. The initial fire is still uncertain. This story was also on HN earlier and Flagged, because of complicated reasons, but it still probably shouldn't have been.

President(*) Trump just suggested the explosion was an attack. Do you believe his "authority" and "credibility" in the matter, over the "fake news" media?

https://www.abc.net.au/news/2020-08-05/donald-trump-suggests...

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

#132
post #88

Earlier quoted context omitted.

Some chemist acquaintances of mine suggested the same from just looking at the footage immediately after. Along with some scary explanations of what fast shockwaves like that do to human blood vessels. I was convinced this stuff should be outlawed for most uses pretty fast. https://en.wikipedia.org/wiki/Ammonium_nitrate_disasters Though on the other hand, the number of incidents and deaths aren't that high considerin…

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

Ammonium nitrate, and ANFO is one of the safest non-military explosives.

And following this, it is one of the most casually, and carelessly treated.

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

#133
This seems unlikely.

Officially, they had 2750 tones of ammonium nitrate on that dock. Even if it were properly mixed with fuel oil to make ANFO, that would give you 2200 tones of tnt equivalent. It is quite unlikely that it was mixed to the perfect proportions, so we’d expect actual yield to be below theoretical max

So unless if something else was involved (or the official amount of ammonium nitrate was wrong) I would expect the final blast to be under 2kt.

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

#134
post #56

This video [1] from The Guardian include the same video in that tweet, but also has a few other angles which gives a better appreciation of how big that thing was. [1] https://www.youtube.com/watch?v=93tV6-0Ugwk

This video is the one that made me gasp the hardest: https://twitter.com/FadyRoumieh/status/1290670721488900096 Something about the distance and the fact that it's on water puts everything into stark relief.

The interesting part about the explosion in the video is that there's two clouds: first the rapidly expanding almost perfectly spherical white puff, and then the slower dark black mushroom cloud. I vaguely recall the first is mostly water vapor that suddenly condenses out of the air because of the massive shockwave, while the second is the 'actual' explosion and its byproducts being shot up into the air. Any physicists out there care to set me straight?

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

#135
post #105

Earlier quoted context omitted.

You can decrease such risks by mixing carbonate minerals (calcium-carbonate and magnesium carboante) into the AN fertilizer, as done in EU counties (and probably in the rest of the world as well).

Isn't it also used as a cost effective explosive in some places? I mean, perhaps thats the reason it was not made inert when it was fabricated in Ukraine. It was on the Lebanese authorities to properly store or dispose of it after they seized the shipping.

It's mixed with diesel and used as a quarrying explosive.

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

#136

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…

  Hezbollah use Ammonium Nitrate
Hezbollah also uses Toyota trucks, but not every fatal Toyota accident in Lebanon is a targeted attack. Millions of tons of ammonium nitrate are produced every year. It has several nonmilitary uses in explosives and fertilizer.

  If you want a source,
  the President of the United States said
The current President of the United States is not a reliable source of information.

  Equally arson or a fire due to lack of security
  and maintenance due to coronavirus stress.
It seems counterproductive to speculate about this on the internet, given what little we know.

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

#137

@quantian1 correctly determined that this was an ammonium nitrate blast by analyzing the footage: https://twitter.com/quantian1/status/1290695231910875136 CHEMISTRY FACT: Explosives have characteristic "detonation velocities" at which shockwaves expand. Smartphone video records at 30 FPS, so the adjacent frames here suggest the front expands at ~100 m/(1/30 sec), or 3,000 m/sec. Consistent with ammonium nitrate, not…

You could tell it wasn’t a military explosive by the noise. Military explosives tend to be of the high speed type, and tend to make a sharper snap. This looked and sounded more like what you’d see in mining, which is pretty close since ANFO (made with ammonium nitrate) is indeed a mining explosive.

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

#138

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…

http://washingtonindependent.com/large-explosion-in-beirut-l...

Many angles here as well

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

#139
post #44

I am seeing other analyses that put the size of the explosion at about one tenth of this size. The analysis in this Twitter thread correlates the observed degree of damage with the distance from the explosion. It comes up with an estimated 240 tons TNT-equivalent, though naturally this comes with a considerable margin of error. https://twitter.com/GeorgeWHerbert/status/129071971954515968... This Twitter thread is mak…

2750 tons of AN perfectly mixed to make ANFO only gets you 2.2kt. So unless if the actual amount of AN was higher, or something else detonated with it, 2.2kt is probably our theoretical ceiling.

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

#140

@quantian1 correctly determined that this was an ammonium nitrate blast by analyzing the footage: https://twitter.com/quantian1/status/1290695231910875136 CHEMISTRY FACT: Explosives have characteristic "detonation velocities" at which shockwaves expand. Smartphone video records at 30 FPS, so the adjacent frames here suggest the front expands at ~100 m/(1/30 sec), or 3,000 m/sec. Consistent with ammonium nitrate, not…

Trump is saying that military intelligence indicates that it's a bomb: https://m.youtube.com/watch?v=tPvH-CqH7Q8 Edit: why am I being downvoted. I am not agreeing with him or saying he is right. Just stating what was said. It seems noteworthy that the president of the US commented on it regardless of accuracy or trustworthiness.

Unverified and likely false information (fake news) is downvoted. If you question the accuracy of the information it's better, still not good, but you didn't before your edit.
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