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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

#111

Post by gonzo41 »

menybuvico wrote: post #106
zsellera wrote: post #94

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).

Not to mention that you don't need to store 2750 tonnes of it in a warehouse in a harbour in a large city like Beirut.

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.

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

#112

Post by p1necone »

moksly wrote: post #108
colordrops wrote: post #96

Earlier quoted context omitted.

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.

Why is Trump used as a source on HN? I don’t think I’ve ever seen that man say something that was useful or true. I’m not American, mind you, so I’m certainly biased because he’s mainly in our media when he does something stupid, but everything I have ever heard him say about Europe has been so far from the truth that it’s hard to take his word on anything.

I think not being American is a useful precursor to saying useful things about Trump, that way you aren't quite as close to the political tribalism that causes people to think "both sides" should be taken seriously.

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

#113

Post by throwaway_pdp09 »

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…

(utter newbie here):

"Explosives have characteristic "detonation velocities" at which shockwaves expand"

but the detonation velocity isn't that; from https://en.wikipedia.org/wiki/Detonation_velocity "Explosive velocity, also known as detonation velocity or velocity of detonation (VoD), is the velocity at which the shock wave front travels through a detonated explosive."

I assume that for an infintely sharp explosion, the shock front would rapidly decelerate to something resembling the speed of sound in the medium? - I can't imagine a shock front in the air at 3km/sec (~ 2 miles/sec) not totally utterly destroying everything, be it building or large living organism, literally shredding it.

Are you sure that's right?

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

#114

Post by forgot_account »

jwilliamson wrote: post #64
jcranmer wrote: post #55

Earlier quoted context omitted.

Naval ships are generally spaced at about "I can see the nearest ship to me in my binoculars"-distances. To give a sense of scale, the USS Washington firing on the IJN Kirishima in the Second Battle of Guadalcanal is reckoned as one of the shortest-range engagements in WWII... at about 5km. That said, the remaining ships in the area were the surviving Japanese destroyers, and destroyers closing in closer to ships wou…

Some WW2 battles were fought at significantly shorter ranges than that. Just in the Malta campaign, at Cape Passero the Italians closed to around 1700m before opening fire. In the attack on the Tarigo convoy, the British closed to 1800m before opening fire and approached as close as 50m to the Italian ships.

Another good example is the Battle of Cape Matapan where British battleships obliterated Italian cruisers at 3500m, at night, in a few minutes.

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

#115

Post by raducu »

grogenaut wrote: post #69
aaomidi wrote: post #37

Earlier quoted context omitted.

Longer fire = less energy for explosion?

High explosives burn too fast for regular flames and suck the oxygen out for subsequent burning. Though you can definitely see fire in the first few frames. https://en.m.wikipedia.org/wiki/Red_Adair got famous for putting out oil well fires with high explosives. Explosives on burn that fast due to their chemical structure not because of free oxygen in the atmosphere. So if you see a fireball, the explosion has slowed…

But I think the guy did that, it just took him a couple of seconds to register.

Remember, you knew it was an explosion before watching the video.

I remember I got the same reaction, but I've watched the video multiple times, I think the first time I would have been as slow as the guy filming.

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

#116

Post by lazyjones »

rsynnott wrote: post #45
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…

> So we either believe official statements The closest to an official statement (US dept of defence officials to media) is that it is not thought to be an attack, Donald’s ex-cathedra ramblings notwithstanding. Nasty accidents at fertiliser plants are unfortunately somewhat common; they dominate the list of largest non-nuclear explosions. Also, why would you steal fertiliser from a fertiliser factory? Traditionally,…

> The closest to an official statement (US dept of defence officials to media)

Where is this press release from the US Dept. of Defence? Or are you talking about the mysterious "three unnamed defence officials" CNN wrote about in an article?

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

#117

Post by DEADBEEFC0FFEE »

gonzo41 wrote: post #111
menybuvico wrote: post #106

Earlier quoted context omitted.

Not to mention that you don't need to store 2750 tonnes of it in a warehouse in a harbour in a large city like Beirut.

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.

How many near misses.

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

#118

Post by colordrops »

p1necone wrote: post #110
colordrops wrote: post #96

Earlier quoted context omitted.

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.

Trump is not a reliable source for anything. He lies/misleads more than he tells the truth whenever he's talking about something verifiable as far as I can tell.

I agree with you, just thought his statement was related and noteworthy.

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

#119

Post by TazeTSchnitzel »

peteretep wrote: post #99
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…

> help directly You could do much worse than donating to the Red Cross and selecting “Disaster Relief”, and if you want to take an action, call your representatives and let them know how important you’d find a robust USAID response. Neither are sexy options, but both will have an effect https://www.redcross.org/donate/D072002.html

That's the American Red Cross though, will the money go to Lebanon?

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

#120

Post by nerdponx »

peteretep wrote: post #99
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…

> help directly You could do much worse than donating to the Red Cross and selecting “Disaster Relief”, and if you want to take an action, call your representatives and let them know how important you’d find a robust USAID response. Neither are sexy options, but both will have an effect https://www.redcross.org/donate/D072002.html

Does MSF have operations in Lebanon?
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