First off…  any spambots reading this should immediately go here, here, here,  and here.  Die spambots, die!  And now…  the winning entries in the Watcher’s Council vote for this week are Chaos or Community by Done With Mi…

First off…  any spambots reading this should immediately go here, here, here,  and here.  Die spambots, die!  And now…  here are all the links submitted by members of the Watcher’s Council for this week’s vote. Council li…

Thanks for the additional info. My metric conversion table gives me about 144 lbs for 65 Kg’s.

Of course, the polonium (or cadmium is another neutron tamper used) has to be set a precise distance from the mass and then brought in closer proximity in order to bombard it with the neutron bath. That kind of design takes many months of testing in order to come up with the proper distances.

Rick, I see the 65 kilogram figure all over the place on the web (the south african gun-design weapons were supposedly slightly more frugal (more highly enriched) at 50 kilograms) - “The device [hiroshima bomb] contained 64.1 kg of highly enriched uranium, with an average enrichment of 80%. The six bombs built by the Republic of South Africa were gun-assembled and used 50kg of uranium enriched to between 80 percent and 93 percent in the isotope U-235.”

(I realize now I am woefully ignorant of weapon design.) The same article has a simple table:
Uranium-235 Plutonium-239

Bare sphere: 56 kg 11 kg
Thick Tamper: 15 kg 5 kg
Where a tamper serves the dual purpose of neutron reflection and increasing the time the unit stays assembled before blowing apart.

Niall Fegurson is betting on 2007.

“First, it’s worth emphasizing that enriching uranium and spinning gas centrifuge machines are necessary but not sufficient steps toward making A-bombs. The Iranians have to operate a cascade of machines. As David Albright of the Institute for Science and International Security points out in a paper published this month, the Iranians tried this once before, in 2003, but failed miserably and broke about a third of their centrifuges in the process. Repairing the damage and getting the machines running again will take at least six months to a year. And it will take another two years beyond that before the plant starts churning out bombs. In other words, if diplomacy has a chance to work, there is some time to make it work.

How will we know, at what point can we judge, whether diplomacy is feasible or fantasy? Several Israeli officials have said publicly that, once the Iranians successfully operate a cascade of centrifuges, even in small numbers, they will know how to operate cascades in large numbers; they will be self-sufficient in the art and science of building A-bombs; they will have crossed a “red line” or, as some ominously put it, a “point of no return.” In other words, from the viewpoint of many Israelis, the question—can diplomacy work?—will be decided in 2006.”

The mission inside the preformation of Radical Islamofascism is but a loop… playing out the synchronicities of former regimes. This time, the stakes are higher with nuclear weaponry.

There are several important challenges when attempting to figure out what the Iranians are doing. First is our lack of data. What we know is like moutain peaks that rise above a layer of clouds - it’s an incomplete picture at best. Some of the reason for the various predictions on capability come from the differing assumptions one is forced to make because critical information simply isn’t available. That said, I tend to agree with a 2-3 year timeline based on what we know, but it’s always possible the Iranians have a separate, covert enrichment program that uses centrifuges or another enrichment technology that may have already given them a crude bomb, or perhaps one this year.

The second, and in my mind, largest, factor in determining the state of the Iranian program is intent. We simply don’t have a good idea what Iran’s true goals are. I think it is safe to assume that Iran wants a nuclear weapon, but that is only the minimum we need to know. What is their ultimate goal? Do they simply want a handful of weapons to guard against their nuclear neighbors Pakistan, Russia and Israel? Or do they want 30 weapons with a capability to produce several a year? What capacity for production do they want - there is a big difference in how they will prosecute their program depending on these goals.

Another important consideration is how they intend to weaponize these bombs. It’s assumed that Iran eventually intends to put weapons on their ballistic missiles, but that goal is a very difficult engineering problem that will take them some time to overcome. Is that their ultimate goal? Or will they limit themselves to another, less challenging (from an engineering perspective) method of delivery. Their options in this area are limited, since their Air Force lacks the capability to reliably deliver a weapon to a target in another country.

The answers to these unknowns will determine how the Iranian’s program will manifest, because they will determine the technical aspects of the program.

I’m short on time at the moment and will try to go into greater detail later.