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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

#91

Post by BoorishBears »

082349872349872 wrote: post #87
chmod775 wrote: post #83

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…

What do you recommend using for fertiliser in its place? (I'm sure someone's thought about this idea before. Timothy McVeigh did his mad bombing with typical rural materiel. Not so fun fact: the VBIED predates the internal combustion engine.)

I think there's some meta commentary here, having someone propose "this dangerous stuff might be getting clamped down on soon".

One of the most important materials in the history of modern civilization, that enabled us to get to a place where we can all sit around on HN and not worry how our food is grown

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

#92

Post by jandrewrogers »

IAmGraydon wrote: post #61
jcranmer wrote: post #39

Earlier quoted context omitted.

From what I understand, ammonium nitrate isn't particularly flammable, until it gets hot--then it gets explosive. Furthermore, ammonium nitrate conflagrations tend to give a distinctive reddish smoke cloud. The cloud accompanying the big explosion has a very distinct red tint to it, indicating that it's a result of the ammonium nitrate going off. That before it doesn't, which suggests that the ammonium nitrate wasn't…

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.

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

#93

Post by zaarn »

golemiprague wrote: post #54

what was the white ball during the explosion? it looks like some liquid spraying up in the shape of a ball, was it sea water? other liquid? or was it just looking to me like a liquid but actually was gas of something?

The white ball is water vapor that condenses into a cloud around the explosion as the shockwave passes through the air. Specifically it's the low-pressure area that comes after the initial shockwave, the rapid decrease in pressure causes water (and any other volatiles) to condense out.

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

#94

Post by zsellera »

nradov wrote: post #88
chmod775 wrote: post #83

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.

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).

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

#96

Post by colordrops »

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…

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.

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

#97

Post by erk__ »

colordrops wrote: post #96
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…

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.

Unnamed defence officials are contradicting it say they have no idea what he is talking about.

https://edition.cnn.com/2020/08/04/politics/defense-official...

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

#98

Post by a_e_k »

jabl wrote: post #81
grogenaut wrote: post #69

Earlier quoted context omitted.

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…

> In those videos when the white large cloud comes out (likely some form of the air being hyper compressed by the shockwave and forced faster than the speed of sound) The white cloud is due to the shockwave causing moisture in the atmosphere to condense. Or rather immediately after the shockwave in the low pressure region. You can see the same effect sometimes due to supersonic aircraft.

Also known as a Wilson cloud: https://en.wikipedia.org/wiki/Wilson_cloud

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

#99

Post by peteretep »

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

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

#100

Post by redis_mlc »

jcranmer wrote: post #55
justinclift wrote: post #49

Earlier quoted context omitted.

On that note, I wonder how the ships / watercraft in the area handled it. Overturned/sunk/? :(

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…

The WW2 battle of Leyte Gulf was fought between US destroyers and Japanese cruisers at very close range - the cruisers couldn't aim low enough to hit the destroyers, while the destroyers raked the cruisers topside with 5" guns.

Also in the WW2 battle of Singapore, two British battleships were sunk by Japanese bombers, but the Japanese ships were very close to the British fleet at times. The result was that Japan dominated both the Pacific and Indian oceans until Midway.

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