Thursday, October 12, 2006
Advice to the Norks: Next time, let a little radiation leak out
There continues to be enormous skepticism that North Korea in fact detonated a nuclear device on Monday. It looked hinky from the very beginning, insofar as the North Koreans went out of their way to declare that there had been no radiation leaks, as if they wanted to pre-spin the findings of foreign intelligence agencies that would be looking for, and not finding, a signature. By the middle of the week, most analysts had decided that the test was either a failure or fraudulent from the get-go. The North Koreans managed to appear crazy-stupid instead of crazy-scary, and have humiliated China, bolstered the hawks in Japan, and made George W. Bush look smart to everybody but the New York Times and various Democrats, who continue to think that it makes sense to "negotiate" alone in a room with a madman.
Against that backdrop, Stratfor reports two little items in its morning "Situation Reports":
NORTH KOREA: No abnormal radiation levels have been detected at the suspected site of a claimed North Korean nuclear test, South Korea's Science and Technology Ministry said. The report follows a similar finding by a South Korean nuclear institute.
NORTH KOREA, SOUTH KOREA: The South Korean government is trying to confirm intelligence reports that indicate North Korea could conduct another nuclear test in the next three days, Seoul newspaper Munhwa Ilbo reported, citing informed sources.
One can't help but wonder whether the Norks won't let a little radiation leak out the next time they "test" a nuclear weapon. I would if I were them, if for no other reason than to create more confusion about their actual capabilities, which are looking pretty pathetic at the moment.
9 Comments:
By 
Georg Felis, at
Thu Oct 12, 01:15:00 PM:
Radioactive fallout from a nuke is a remarkably complex mixture of short-lived isotopes and tiny fragments of the original fissile material and surroundings. It would be easy to date and almost impossible to fake, even harder than Photoshop. Perhaps that is why their first “Test” did not leak, they were afraid of being found out.
By TigerHawk, at
Thu Oct 12, 02:56:00 PM:
Interesting. What are the odds that none leaked out the first time?
By Charlottesvillain, at
Thu Oct 12, 04:59:00 PM:
Maybe if we keep pretending we didn't notice anything they will use up all their bombs in the mine.
By Lanky_Bastard, at
Thu Oct 12, 05:42:00 PM:
Was this supposed to be plutonium or uranium?
By Dawnfire82, at
Thu Oct 12, 07:30:00 PM:
I'm not sure they've ever done us the favor of telling us, but if memory serves all the negotiations during the 90's dealt with uranium reactors.
By 
, at
Thu Oct 12, 08:02:00 PM:
It would make sense that it would be a plutonium bomb. You have to be really stupid to screw up uranium, and they're simple enough that they really don't need to be tested anyway.
By , at
Thu Oct 12, 08:33:00 PM:
Thanks for that insight, Dr. Oppenheimer!
Really, I find it continuously fascinating the incredible expertise in isotope separation science, operation of enrichment reactors and weapons designs that show up on so many blogs. There must be an incredible number of frustrated nuclear physicists out there working at something other than Nuclear Physics these days.
Just as an aside, two of my undergraduate physics teachers (both Ph.D's in the '70's) were young physicists who worked in the Manhatten Project in the '40's, and although they did what would seem very mundane work on the project, they were both remarkably intelligent men (no kidding, and I'm not a physicist, either). I doubt they would think that some of the engineering and design features of setting off an A-bomb were that elementary.
There are a myriad of basic science and engineering problems that could baffle and create failures in any A-bomb project. My guess is that although N Korea is actually trying to build an A-bomb, that this event of Oct. 8 was an elaborate hoax, which has a political component to it to help 'Lil Kim.
A plutonium bomb requires implosion, which can be tricky in a technical sense, in making the implosion work exactly right to achieve fission; plus the plutonium isotopes DO have to be relatively pure, but are somewhat easier to make by neutron bombardment in a reactor.
A uranium bomb is hard to make, in that the isotopes require much more work to isolate (U-238 and U-235). The design is simpler, but can fizzle if, again, the isotope purity is not adequate.
The smaller the A-bomb, the trickier it is to achieve the necessary neutron flux when the critical masses are shoved together (plutonium bomb or Uranium bomb). So although some think that the NoKo's are really clever in making a small nuke warhead, it looks a little funky to me. No radiation measurable in the air? I have a nuclear physicist friend that works in non-proliferation at Los Alamos, and she would probably say "not possible". Airborne detection systems are incredibly sensitive, and downwind of an underground test would measure SOMETHING.
-David
By Georg Felis, at
Thu Oct 12, 10:43:00 PM:
Actually Anonymous, many of the readers of excellent blogs such as this are quite educated and knowledgeable in the basics of many sciences (but not the exact specifics). We may not be able to separate Uranium in our kitchen sinks, but we have a fair idea of how it is done.
An obsolete gun-type Uranium bomb is bulky, difficult and expensive to create, but fairly trivial to set off since you are just smacking two sub-critical masses of U together. In theory you could do it by hand with a miniscule yield of a few tons and a lot of wasted nuclear material. It almost happened by accident once. http://en.wikipedia.org/wiki/Louis_Slotin
North Korean nuclear program problems include poor quality control, contaminated fuel, and a rather erratic nut in charge, but they have the advantage of the Dr. AQ. Kahn technical research information, and pre-made implosion bomb designs. Plus to my knowledge, there has never been a nuclear test that has failed completely. There have been some “fizzles”, but even 10 kilotons instead of 50 will ruin anybody’s day.
By , at
Thu Oct 12, 11:55:00 PM:
David, just because you might not understand something doesn't mean other people who read this blog can't understand it either.
"The scientists who designed the "Little Boy" weapon were confident enough of its likely success that they did not test a design first before using it in war. In any event, it could not be tested before being deployed as there was only sufficient U-235 available for one device.:
http://en.wikipedia.org/wiki/Nuclear_weapon_design#Gun_method
