How big is a dirty bomb, or nuke?

[Tmy]

We always hear stories about the threats of dirty bombs, or terrorists getting their hands on a nuke. Lets say they did. Practically speaking, can you just walk around with these things??? How big and complicated would these things be.

I cant imagine a nuke can fit a suitcase.

 

[Bikewer]

A "dirty bomb" is just a conventional explosive in proximity to some radioactive material; it's designed to disperse the material, and contaminate a large area.
Most analysts say that this sort of thing would be far more effective as a terror or psychological weapon than as a casualty-producing device.
Most of the types of material terrorists might get hold of are not particularly lethal in terms of thier radioactivity level. Note that such devices are not "nukes", no fission or fusion takes place.

Actual nuclear weapons can be pretty small. The US has built a wide variety of small warheads that can be fitted to fighter-launched missiles, for instance.
The "Davy Crockett" tactical weapon I was familiarized with back in the 60's had a warhead that was maybe 12" in diameter and 24" long, and that included the casing.
The megaton-range MIRV (multiple independent re-entry vehicles-don'tcha love acronyms?) warheads are not much bigger, and an ICBM can carry a bunch.
There are numerous reports of "suitcase" nukes, which mean really human-portable. Supposedly intended for battlefield demolitions.....Right.

Anyway, sure. The essential features are a critical mass of plutonium and sufficient explosives to cause the implosion, with the attendant wiring and detonators.

 

[Tmy]

Ok sio there is such a thing as a suitcase nuke. Id imagine that they would be few and only accessable by the advanced nuke countries. And less likely to fallinto terror hands. Wouldnt your black market nuke be likey to be a big clunky old school bomb.

 

[Mycroft]

Ok sio there is such a thing as a suitcase nuke. Id imagine that they would be few and only accessable by the advanced nuke countries. And less likely to fallinto terror hands. Wouldnt your black market nuke be likey to be a big clunky old school bomb.

So if you had a big clunky old-school bomb, how hard would it be to stick it in a cargo container, put it on any ship and sail it into any harbor city in the world? You could detonate it before any customs agent has a chance to read the cargo manifest.

 

[MRC_Hans]

For terrorist purposes, you should add some amount of screening. Not so much to protect the carriers (I don't suppose they care about that), but to keep the device from being too detectable. A compact nuclear device without any screening will emit radiation that is detectable at considerable distance, probably even from helicopter range.

Hans

 

[Jon_in_london]

Dirty bombs are enirely psychological, at least the dirty bit is... All the fatalities that occur will be due to the good old high explosive and the 'dirty' bits will just take a bit more cleaning up than normal. Of course the knee-jerking public will be having hysterical fits about chernobyl and hiroshima all the time but not much damage, if any at all, will be done by the radiation.

 

[bangdazap]

There are numerous reports of "suitcase" nukes, which mean really human-portable. Supposedly intended for battlefield demolitions.....Right.

There are small 1 kiloton nuclear devices (footlocker size) inteaded to demolish ammunition depots. I guess If you can make nuclear artillery shells and torpedos a nuclear "suitcase" isn't a problem.

 

[varwoche]

Dirty bombs are enirely psychological, at least the dirty bit is... All the fatalities that occur will be due to the good old high explosive and the 'dirty' bits will just take a bit more cleaning up than normal. Of course the knee-jerking public will be having hysterical fits about chernobyl and hiroshima all the time but not much damage, if any at all, will be done by the radiation.

Isn't it true that a dirty bomb could render the immediate area uninhabitable for a period of years?

 

[aerocontrols]

Isn't it true that a dirty bomb could render the immediate area uninhabitable for a period of years?

Not very practically, no.

Although a dirty bomb could render the immediate area politically unihabitable, perhaps forever.

Nobody lives near Chernobyl, for instance, though anybody could. Most of the people evacuated from Chernobyl should have been left alone.

 

[Agammamon]

Depends on how well you clean the area up. Of course there's the psychological effect in that people won't want the area no matter how well it is actually cleaned.

Remove the contamination that comes from the fissionables in the bomb itself and the vast majority of your problem goes away. This stuff will irradiate the material around it but at low levels and short half-lives.

Shielding against dectection could be a problem. The types of radiation that are most detectable at a distance are also the types that are the hardest to shield against.

 

[Bikewer]

The bomb-in-the-shipping container is a truly frightening prospect.

There are all sorts of freight lines that have little or no security, or who might be co-opted or bribed. If a "strategic" weapon were exploded in New York harbor or San Francisco bay, the results would be devastating.

As noted, you wouldn't need to get anywhere near customs; just crank it off in the harbor.

Government officials are aware of the problem, but the scale is enormous. Thousands of ships unloading more thousands of containers.

 

[varwoche]

The bomb-in-the-shipping container is a truly frightening prospect.

You ain't kidding. Of course here on Puget Sound, WA we have not only the bad guys to worry about, but also good guys with bad hands.
off-topic article

 

[Jon_in_london]

Nobody lives near Chernobyl, for instance, though anybody could. Most of the people evacuated from Chernobyl should have been left alone.

I dont think thats entirely true- the radiation levels in the surrounding areas were quite phenomenal and still are inside houses in the nearby city.

However, I agree that a dirty bomb cant do something like that.

Its important to remember that Chernobyl was like this really humginourmous building stuffed with high grade uranium and if you tried to take it with you onto the underground/metro/train I think someone might notice that something isnt quite right, and might possibly raise the alarm. Besides, I doubt that it would fit through the ticket gates.

 

[aerocontrols]

I dont think thats entirely true- the radiation levels in the surrounding areas were quite phenomenal and still are inside houses in the nearby city.

By 'nearby city' you would mean Pripyat, therefore not including most of the people evacuated due to the accident?

I would not suggest that Pripyat (50,000 people) should not have been evacuated temporarily, or even perhaps permanently, but that the other 288,000 were (and remain) another story.

The main cause of health problems due to Chernobyl seems to have been the forcible relocation of the extra quarter of a million people due to over-reaction to the dangers of radiation.

Read here for the UNSCEAR report or read this article by the former chair of UNSCEAR. Findings: no measureable increase of cancer or other sickness in the adult affected populations, beyond the couple of hundred that went on-site to put out the fire, etc. An increase in thyroid cancers (which may or may not be attributable to Cherynobyl) for children, of which said increase has, as of 2001, killed 1 [sic] child.

I realize that your counter could be to argue that the evacuation of the other 288,000 people is precisely what minimized the cancer deaths. To respond to that, I direct you to what Dr. Zebigniew Jaworowski says in the article I linked to above:

Thus, in the special case of Pripyat, one can say, that the early decision to evacuate the inhabitants of Pripyat was well conceived, and correctly performed. But most of the other evacuations were unnecessary, erroneous, and harmful.

However, I agree that a dirty bomb cant do something like that.

Its important to remember that Chernobyl was like this really humginourmous building stuffed with high grade uranium and if you tried to take it with you onto the underground/metro/train I think someone might notice that something isnt quite right, and might possibly raise the alarm. Besides, I doubt that it would fit through the ticket gates.

I think the fear is that someone will try to use a 'dirty bomb' to shut down a port, which would be easier to 'sneak into port', but I still don't think it would work.

As a matter of fact, I believe so strongly that it would not work that I openly hope that this is exactly what terrorists are working on, rather than something else that might actually kill thousands. The biggest dud of all time.

 

[Beerina]

Ok sio there is such a thing as a suitcase nuke. Id imagine that they would be few and only accessable by the advanced nuke countries. And less likely to fallinto terror hands. Wouldnt your black market nuke be likey to be a big clunky old school bomb.

I recall a small news story from some months after 9/11, that reported the US had a talk with Russia and China, wherein they basically forced them to help track such small things, hinting that were any to get into hands of terrorists and used, well, nudge-nudge, wink-wink, remember Kennedy's famous line in the Cuban missle crisis?

 

[Beerina]

For terrorist purposes, you should add some amount of screening. Not so much to protect the carriers (I don't suppose they care about that), but to keep the device from being too detectable. A compact nuclear device without any screening will emit radiation that is detectable at considerable distance, probably even from helicopter range.

Hans

One hopes the government has recently produced sensitive nuke-sniffer trucks that they drive up and down major city streets, especially NY and DC, on a regular basis.

They did detect radiation on that cargo ship last year, and held it offshore some miles while investigating further. I think they thought it was residual radiation from regular ore, a normal thing, but I never did hear a follow up to the story.

 

[Bikewer]

There was a story a while back about a guy getting "detected" at the border crossing to Mexico; he had radioactive isotope treatments for a scan. That's pretty sensitive!

 

[richardm]

It seems that the threat from terrorists with Nuclear, Biological and Chemical weapons is rather over-rated. Nuclear - you can't feasibly make a "proper" atomic bomb and if you could it would be hard to deliver. A stick of dynamite with some uranium wrapped round it won't have any great effect. Chemical weapons appear ineffective unless you have extremely large quantities (note the effect that Sarin had when it was used in Tokyo - viz. Not very much, really). Biological weapons are difficult to organise in ways that affect lots of people.

Are the threats really so small?

 

[Thanz]

As a matter of fact, I believe so strongly that it would not work that I openly hope that this is exactly what terrorists are working on, rather than something else that might actually kill thousands. The biggest dud of all time.

I must vehemently disagree with this sentiment. I do not think that you are looking at the broader picture and what the effect of such an attack would be on global trade. International trade with the US would come to a sudden halt and the economy would go into the toilet.

Remember all of the extra security that the gov't put into place after 9/11 at the airport? Taking off your shoes, taking your nail clippers, etc. The tourism industry was hit hard, and the travellers who still went places were hit with inconvenience and delay. Well, that's nothing compared to what would happen to shipping. At present, only a small fraction of containers are inspected. There would be calls for inspections of all containers - causing unbeleievable delays and costs.

The effect on the economy would be nothing short of devastating.

 

[Bottle or the Gun]

All you really have to do is grind a few ounces of Plutonium to powder and dump it off a tall building. There goes New York.

A 'dirty bomb' is more psychological. A pound of material blown up with conventional explosives and there goes both the tourist trade and the cancer rate.