Iran and centrifuges
The Iranians claim to have produced enriched uranium "to the 3.5% level". That is pure enough to use as nuclear fuel, though nowhere near what would be needed to make a bomb. Experts say the bank of 164 centrifuges that the Iranians used is not enough to churn out significant amounts.
Interesting stuff on exactly the scale of Iran's operations.
At the start it is typically less than 1%; the Iranians say they have increased that to 3.5%. What worries the US is that, should the Iranians add more centrifuges, they may have the potential to enrich this fuel-grade uranium to weapons-grade uranium, which requires 80-90% uranium 235. Even then, they would need 50kg of this highly enriched uranium to achieve a viable atomic weapon.
Frank Barnaby, a nuclear physicist at the UK Atomic Weapons Establishment in the 1950s, said: "If they've enriched some uranium and measured the enrichment then that's quite a way down the line. But 164 centrifuges is negligible, you'd need thousands to get significant amounts of weapons grade uranium." Satellite images suggest the enrichment plant at Natanz could house 50,000 centrifuges.
The domestic ore the Iranians are believed to be using would pose a problem, Dr Barnaby adds. "The Iranian uranium is contaminated with molybdenum and other heavy metals and that would tend to gum up the centrifuges and limit the degree of enrichment to far below the weapons grade level."
The point is that Iran has spent years getting up to 164 centrifuges, and that is barely enought to produce low grade nuclear plant fuel. Military grade material will require thousands to produce.
The subtle but important side effect of that is what makes taking it out with bombs so hard. Thousands of centrifuges in seperate underground bunkers, plus empty bunkers and other deceptions, make taking out the facility via bombing very difficult.
Jay