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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

#171

Post by dzhiurgis »

codebolt wrote: post #122
gonzo41 wrote: post #111

Earlier quoted context omitted.

The natural heat was the killer. IF twitter was right the fire started from sparks from a welding on a door. The AN must have already been decomposing in the heat and under weight just waiting. I wonder how often this storage facility was at a critical point like this. Like how many hot days. How often before this. It makes you think about all the other risks sitting out there just waiting for a small spark.

There was also fireworks going of just before the blast. Storing 2750 tons of AN next to a fireworks cache seems cartoonishly stupid. https://twitter.com/ConflictsW/status/1290681902781861888?s=...

Well it's not really that easy to detonate AN, there are quite a bit of variables that come together.

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

#172

Post by mytailorisrich »

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.

The reports say that this is the result of ~3kt of ammonium nitrate.

So are they saying that ammonium nitrate is equivalent to TNT?

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

#173

Post by linschn »

madaxe_again wrote: post #156
sillysaurusx wrote: post #76

@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…

There’s an even easier giveaway - the bloody great cloud of NO2 that immediately appears. I think anyone who’s ever seen a fertiliser dump go up will have immediately recognised this explosion - reminded me of my childhood, when we’d regularly go and explode things with the stuff.

Indeed, it immediately reminded me of the cloud I saw above Toulouse, France in 2001 when the AZF factory exploded. Same product.

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

#174

Post by lma21 »

I have family and friends living in Lebanon. The explosion destroyed the windows of most homes in Beirut. Apartments of my family, friends, and colleagues have been shattered. Even the ones living dozens of kilometers away from Beirut. It's horrible, what pure incompetence can do to a people already living in poverty and under the covid-stress. I hope something good comes out of this...

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

#175

Post by TooSmugToFail »

ashtonkem wrote: post #137
sillysaurusx wrote: post #76

@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.

But what about the regular shape of the blast?

Looking at the videos of Tianjin disaster, there are multiple large explosions, each with a massive fireball, highly irregular, fiery projectiles flying everywhere etc.

The massive blast in Beirut was a singular event, with no preceding or subsequent blasts of similar magnitude. As if the ignition of the material was very efficient.

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

#176

Post by me_me_me »

DonHopkins wrote: post #131
aaron695 wrote: post #32

Earlier quoted context omitted.

> 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...

+1 I would bet my hand that Trump wouldn't be able to roughly point on the map where Lebanon is. But for sure he is the expert on their internal politics and struggles.

I am surprised anyone on HK is considering him as source of any info (unless a bot).

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

#177

Post by ALittleLight »

varjag wrote: post #147
codebolt wrote: post #122

Earlier quoted context omitted.

There was also fireworks going of just before the blast. Storing 2750 tons of AN next to a fireworks cache seems cartoonishly stupid. https://twitter.com/ConflictsW/status/1290681902781861888?s=...

If prior to the explosion you were told that all dangerous cargo is stored in dangerous cargo area of the port, would you've thought it is stupid?

Would I have thought that storing a massive amount of explosives next to flammable material in the middle of a city was a bad idea? Yes.

I don't claim to be a prophet, but it's hard for me to see why anyone wouldn't think that would be a bad idea.

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

#178

Post by lm28469 »

kgm wrote: 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…

> I am seeing other analyses that put the size of the explosion at about one tenth of this size.

Random twitter users are guesstimating from smartphones videos and have 0 knowledge of the actual location, so yeah, it's just guesstimates. I'm still wondering why people do that, it's kind of a weird flex and bring literally nothing of value to the table besides trying to sound like a smartass.

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

#179

Post by lm28469 »

9nGQluzmnq3M wrote: post #134
look_lookatme wrote: post #84

Earlier quoted context omitted.

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 physicis…

> 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.

Not a physicist but yeah, that's it.

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

#180

Post by aaron695 »

kthxbye123 wrote: post #47
aaron695 wrote: post #28

Earlier quoted context omitted.

I'd like to know why it initially sounds like fireworks https://twitter.com/HeshmatAlavi/status/1290683991369097216 [camera operator probably would have died in the second blast] Is that what set it off? Or is that what ammonium nitrate sounds like burning?

Just as an FYI, this account is a well known fake persona run by MEK cultists in Albania, not really a great source of info- note that it immediately began boosting a completely unsubstantiated theory that the explosion was caused by a depot of Iranian munitions.

Thanks.

I did check and it was quickly geo-located -

https://twitter.com/N_Waters89/status/1290688278094647298

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