crocodile deathroll

Building a nuclear bomb may be a lot easier than you think, and you do not need Uranium 235 or Plutonium 239 because there are other isotopes that are fissionable like americium-241.
You can obtain that in the common household smoke alarm, and with 1500 of them you can extract enough americium-241 to create a critical mass.
Read more about it on this webpage.

http://www.webspawner.com/users/nukes/

Arken

I don't know whether or not the science in that article is accurate, but this guy claims he's actually built one of these and he's not sitting in a dark cell somewhere and the website is not replaced with CENSORED BY THE PATRIOT ACT or something?

I call no way.

NumberTenOx

OK, some research.

One gram of americium oxide provides enough active material for more than 5000 household smoke detectors.

Americium 241 is a fissile material, the critical mass being in the region of 80 kg.

So 5000 * 80 = 450,000 smoke detectors, not 1500. Also, it's used as an Americium Oxide compound, which I'm sure is not pure enough to pack into a critical mass, so you'd need many times this number of smoke detectors (say, a million?), and a way of purifying the Americium.

However, you could apparently make an atomic bomb from Americium 241, if you could find the pure stuff. This is apparently a problem because it is not regulated as well as other radioactive material and is available because of its commercial uses, and also because it's sometimes removed from radioactive waste in order to make the waste less dangerous.

So don't worry about smoke detector bombs, but do worry about stores of the real thing hanging around.

Corwin

Ammonium nitrate is also perfectly legal and available to the general public.

If you buy more than about 10 kilos tho.... you get noticed. Buy a truckload? You'd better live on a farm that uses the stuff..... because you WILL get a knock on your door and two nice young men in suits with bulges in the jackets will have a few questions for you.

Yes it's possible to get several radioactive isotopes.... some of them with enough mass to produce a chain reaction. But the odds of getting enough of it without the FBI noticing are slim to none.

Jesse

They said 5000 smoke detectors = 1 gram, and critical mass = 80 kilograms = 80,000 grams, so that should be 450 million smoke detectors, which makes it even less plausible.

echidna

Yes, but it should keep Al Qaeda occupied for a while.

Calzaer

Hey, it'd be a hell of a lot easier than cutting down the Brooklyn Bridge with an acyetalene torch. Maybe they should get a truck driver to look into it.

Elvithriel

Or just hi-jack a truck.

Risiko

According to the High Energy Weapons Archive , Am-241 (the isotope used in household smoke detectors) has an estimated bare sphere critical mass of 84 kg. One smoke detector contains 0.26 micrograms of Am-241. As far as I can calculate, a bomb-builder would need in the order of 3*10^11 smoke detectors. He might be able to negotiate a reduced price, I guess

Quoted from here: "The isotope americium-241 is the most important because of its availability. It has been prepared in kilogram amounts from plutonium ... In Sept. 1998 the ORNL Isotopes Division charged $728.00 per gram of americium-241".

Even if enough AP-241 has been produced to form af critical mass, it would seem to be a mighty expensive thing.

Edited to add: Again according the the HEW Archive, a bare critical mass of Am-241 produces 9.6 Kw of heat.

Risiko

I just went to the link from the OP. Oh dear.
If that guy is serious (and I'm pretty sure he isn't) then at least he has been wasting his time doing something rather harmless.

Am-241 is probably useless in a gun assembly weapon. Its spontaneous fission rate is too high; it'll disassemble before reaching critical mass.