North Korea to make an announcement at 2:30 AM on tonight's nuclear

[applegrove]

Last edited Sun Sep 3, 2017, 02:45 AM - Edit history (1)

test.


Background here:

https://www.washingtonpost.com/world/north-korea-apparently-conducts-another-nuclear-test-south-korea-says/2017/09/03/7bce3ff6-905b-11e7-8df5-c2e5cf46c1e2_story.html?utm_term=.bb06f64c7daf

Update: It was a hydrogen bomb.

[RandySF]

1. It's an H-Bomb on Trump's watch.

[applegrove]

2. How is a hydrogen bomb different than a nuclear one?

[uppityperson]

3. H bombs are more powerful, if the same size

https://www.livescience.com/53280-hydrogen-bomb-vs-atomic-bomb.html

Thermonuclear bombs start with the same fission reaction that powers atomic bombs — but the majority of the uranium or plutonium in atomic bombs actually goes unused. In a thermonuclear bomb, an additional step means that more of the bomb's explosive power becomes available.

H bomb is an A bomb which then uses the rest of the potential in the bomb.

[applegrove]

5. ****ers!

[RandySF]

4. Hydrogen bomb vs atomic bomb.

TOKYO — How powerful are hydrogen bombs? Think of it this way: They use atomic bombs just as a trigger.

Atomic weapons like those previously tested by North Korea rely on nuclear fission to release energy — basically splitting atoms. The bombs dropped by the United States on Hiroshima and Nagasaki during World War II used this technology to release explosive power equivalent to about 15 and 20 kilotons (1,000 metric tons) of TNT, respectively.

Hydrogen bombs use nuclear fusion, in which atoms fuse together, to release even greater amounts of energy. The two-stage process is often referred to as a thermonuclear reaction. The first hydrogen bomb tested by the United States in November 1952 released the equivalent energy of 10,000 kilotons (or 10 megatons) of TNT.


https://www.usatoday.com/story/news/world/2016/01/06/h-bombs-vs--bombs-explained/78347150/

[applegrove]

6. ****!

[KY_EnviroGuy]

7. It is a nuclear weapon - one of several types

Good explanation here:

https://en.wikipedia.org/wiki/Thermonuclear_weapon

Not yet known which type this test used. As I understand it, foreign sensors (maybe in sniffer aircraft or remote ground stations) have to pick up traces of the radioactive particles to tell what materials are used.

Uses uranium or plutonium, so yes, highly radioactive.

[applegrove]

8. Thanks. My brother lives in Japan. His partner is Japanese, and though

she and her family loved Obama, when Trump was elected they hoped he would be strong and could control North Korea somehow.

[KY_EnviroGuy]

32. I can better understand their feelings...

if I just look, by comparison, at a similar situation in the US mainland. If I lived in LA, then North Korea would be the equivalent distance to Albuquerque, new Mexico. That's darn close!

I fear that Trump's bullshit about his deal making skills during the election campaign has a lot of folks fooled. Also not clear on what people mean by a US president being "strong". Our president has no strength without a powerful diplomatic corp, supportive public and Congress, and good array of allies to work with. Trump seems hell-bent on destroying all those things!

[KY_EnviroGuy]

9. Not known...

It's not known at this point what type of device was used. NK president had recently claimed they had an H-bomb, but no one really knows what they have at this point. Kinda like a lot of stuff tRump brags about.

Nuclear experts will determine what type - if meaningful data can be collected remotely from NK.

[applegrove]

10. NK just came out with a statement saying it was a hydrogen bomb.

Japan says it was ten times stronger than previous nuclear tests. The US and allies in the region have sniffer planes that will fly over NK and take samples to test for the make up of the bomb.

[KY_EnviroGuy]

11. Yes, I'm seeing their claim now on BBC.

Will be interesting to see what the expert say about tonnage and type. Would be interesting to know too, what the hell collapsed 8-minutes after the explosion that caused a magnitude 4.1 quake. We'll probably never know unless the satellite boys see something.

We also know to take anything NK says with a grain of salt.

While looking at the USGS earthquake web site on this one, I see the Yellowstone area over on the Idaho side has had a swarm of around 40 quakes, with the largest at magnitude 5.3. Wow!

[RandySF]

12. It registered a 6.3, largest yet from NK.

Also. A weapons expert I follow on twitter did a back of the napkin calculation and estimation the yield to about one megaton.

[KY_EnviroGuy]

13. One of my concerns...

is that NK might explode one of these things in the atmosphere over the ocean well away from land to rattle swords with Trump and of coarse, what the US and China reactions would be. That action alone could plunge the world into economic and political chaos.

Has your Twitter friend ever mentioned that possibility and concern?

[longship]

14. I doubt one megaton.

It was an underground test. One does not trigger a one megaton nuke underground unless one wants to make a rather large crater.

It's about the energy released.

Also, I doubt that the DPRK is being truthful about having an H bomb.

[RandySF]

15. A second earthquake was detected near surface level.

Believed to have been a collapse.

[RandySF]

16. Sournce material. Like I said, back of the napkin for now.

Link to tweet

[longship]

18. My mileage does vary.

Not a megaton. DPRK barely has a fission bomb. No way they have a fusion bomb.

This was a fission bomb that worked, one of their only ones. I guess they have finally figured out the initiator. Either that, or this test happened upon a fortuitous cosmic ray which kicked out the requisite slow neutron or two at just the right moment to start the chain reaction.

Also, I don't think the DPRK knows how to predict the yields of their tests because they've been fizzling.

If this was a megaton yield, they are much more stupid than I thought. Now megaton yield would almost have to be at least part fusion. But I doubt that it is either fusion or megaton, simply because complexity of a fusion weapon is much, much more than a fission device. When we invented ours, they had to come up with new mathematics to design a workable design.

See Richard Rhodes, The Making of the Atomic Bomb, and Dark Sun: The Making of the Hydrogen Bomb

[RandySF]

19. CNN is reporting 120 kt.

[longship]

20. That's more reasonable, and likely not a fusion device.

The question is, what kind of madman would explode that large a bomb underground and not expect the ground to collapse???

Fission bombs are about as hard to do as anything, especially getting the damned things to chain react, as the DPRK now apparently knows. Fusion bombs are really, really much more complex and difficult. They aren't there yet. I suspect that they aren't even close.

I'll wait for the experts' rulings.

[KY_EnviroGuy]

21. Thanks...

...for bringing things into good perspective.

Kim Jong-un is ratcheting up the bullshit. Many experts have been saying there's little likelihood NK has developed a fusion system, much less a miniature one. Let's just hope no other nation has simply outright given them the damn thing.

Any idea of what the margin or error is for using earthquake data for estimating yield? Doesn't that require some knowledge of the device and installation (depth, overburden, etc.)?

Thanks also for the good book references.

[longship]

26. Margin of error?

Not sure. But scientists always specify margin of error or their papers do not pass peer review. They don't pass peer review if the peers disagree with their stated margin of error. It is one of the things that science knows all about that the public does not.

And I agree about Kim Jong Un and his regime.

The thing is... I do not know whether they've figured out the initiator, or they benefited from a fortunate cosmic ray. Almost none of their nuke tests have been nuclear chain reaction level explosions. I think the evidence now is that they've figured it out. But since their previous tests were so low yield, the first several below nuclear level, that they made a rather big bomb to test not realizing that when they do get a good initiator, the bomb is going to finally chain react like gang-busters.

It's Castle Bravo all over again. That's the US nuke test that ran away wild and killed people.

[KY_EnviroGuy]

28. Interesting.

You're suggesting it may even have been an accidental trigger. Probably a bunch of dead folks in the area, then.

I vaguely recall experts saying that one of their early claimed "nuclear" tests was more likely a huge pile of conventional explosives set off underground just to scare the crap out of their adversaries.

Have any thoughts on the 8-1/2 minute delay between quake sensor events?

USGS Data:
Last Updated 2017-09-03 10:08:20 (UTC)

Magnitude / Type / Location / Date & Time / Depth

4.1 Collapse 22km ENE of Sungjibaegam, North Korea 2017-09-03 03:38:31 (UTC) 0.0 km

6.3 Explosion 22km ENE of Sungjibaegam, North Korea 2017-09-03 03:30:01 (UTC) 0.0 km

[longship]

29. Highly unlikely to be accidental.

It would take a truly beneficial cosmic ray. The reason for the initiator is to supply one or two slow neutrons to start the chain reaction at the very precise microsecond of maximum assembly. Without those slow neutrons the assembly would blow itself apart before the chain reaction can get going.

I think that it is much more likely that they have solved the initiator problem, at least partially.

But an order 100Kton explosion certainly indicates that they got the requisite slow neutrons to get their chain reaction. And that is of the magnitude of a rather large fission bomb. Certainly the USA exploded some like that before the fusion bomb was invented.

I'd look at the Bulletin of Atomic Scientists for information in the coming days. I will post an OP if I see anything. They're the experts on this stuff. I am just a sideline observer with a physics degree.

A nuclear explosion has a very specific seismic signature that any seismic physicist would recognize, like those guys at the SoCal Earthquake Center at Cal Tech. I imagine that they could also tell the difference between a fission detonation and a multistage fission-fusion one, just from the seismology. That would also have a unique fingerprint.

[KY_EnviroGuy]

30. Actually, I was thinking...

more in terms of an operational screw-up type of accident, but we may never know with zero transparency. Also, we're unlikely to ever know the damage to the people and villages in the area, or to China's border areas. They must have collapsed a large system of tunnels or very large underground cavern to cause a magnitude 4.1 follow-up over 8-minutes later. Perhaps it could simply be a geological after-shock!

And, I'm finally getting your point about the initiator - primarily meaning a proper one for sizable fission devices, I assume.

Didn't even occur to me about the time-domain waveform of the shock being a specific nuclear signature. Most likely, the USGS and CalTech now have lots of historical signatures as reference. Perhaps not from the 50s though, when we blew up all of our toys.

Thanks for the reminder of http://thebulletin.org/. Have not visited them in a while. Will be watching their articles this coming week. Have a good Sunday.

[longship]

31. Well, if an accident effects China, game over man.

DPRK's experiments in nuclear weapons are over. Xi would never tolerate such a thing. That's why I wonder about the secondary seismic report of a collapse.

A 100 Kton explosion underground is really, really big. I'm not sure, but I don't know if USA ever tested a nuke underground that large. They certainly never did one much larger than that. No wonder there was a 4.1 magnitude collapse afterwards.

I want to see what the seismic experts say about this data.

My best to you.


BTW, without a proper initiator there is no chain reaction at all. The assembled nuclear material blows itself apart before a chain reaction can get started. The bomb never gets going no matter the size of the weapon. No initiator? No nuclear detonation. The bomb fizzles. It is, at best, a dirty conventional bomb. (That's bad enough, but at least it doesn't destroy a city. They'll be some nasty cleanup in an area, though.)

[applegrove]

17. Yes. They say not to worry about Yellowstone. I'm of the frame of mind

that if super volcano Yellowstone blows that it would be better to die instantly than live to suffer with the sun blocked out all over the world. So I'm glad I'm closer to Yellowstone. A few thousand miles away. I would not want to be in Japan. Or anywhere near North Korea with a hydrogen bomb. That sounds like torture to me. I shudder to think the fealty Kim Jong Un will demand of the world now that he is a nuclear power.

[Not Ruth]

22. Guam is next

[Not Ruth]

23. This describes a test of a device with similar yield done by the US, note the collapse that followed

Though performed as part of the Nuclear Weapons Testing Program,[23] "[the] purpose of the Milrow test was to test an island, not a weapon."[26] It was a "calibration shot", intended to produce data from which the impact of larger explosions could be predicted, and specifically, to determine whether the planned Cannikin detonation could be performed safely. Milrow was detonated on October 2, 1969 51°24?52.06?N 179°10?44.84?E, with an approximate yield of 1 to 1.2 megatons (4.2–5.0 PJ).[3][27]

The shockwave reached the surface with an acceleration of over 35 g (340 m/s2), causing a dome of the Earth's surface, approximately 3 km (2 mi) in radius, to rise about 5 meters (16 ft).[28] The blast "turned the surrounding sea to froth" and "forced geysers of mud and water from local streams and lakes 50 feet (15 m) into the air".[25] A "surface collapse feature", also known as a subsidence crater, was formed by material collapsing into the cavity formed by the explosion.[3]

[Not Ruth]

24. 2 years after the 1 megaton test, the US had their largest underground test ever, 5 megatons

Amchitka was selected by the United States Atomic Energy Commission to be the site for underground detonations of nuclear weapons. Three such tests were carried out: Long Shot, an 80-kiloton (330 TJ) blast in 1965; Milrow, a 1-megaton (4.2 PJ) blast in 1969; and Cannikin in 1971 – at 5 Mt (21 PJ), the largest underground test ever conducted by the United States. The tests were highly controversial, with environmental groups fearing that the Cannikin explosion, in particular, would cause severe earthquakes and tsunamis.

[Not Ruth]

25. Note that the US had the 5megaton to be tested, they were afraid to do that, so they tried 1megaton

Which means that NK may have a 5 megaton hydrogen bomb ready to go.

[RandySF]

27. If you want to know what a 120 kt blast can do in your hometown.

https://nuclearsecrecy.com/nukemap/