Foreign Correspondence

[otraque]

Here is good and valid account of the description of the high degree of difficulty to get the needed refinement to get what makes a bomb.
What we do NOT know is what those are guessing at, and that is how many centrifuges does Iran have.
When Israel says they believe Iran is but months away from the bomb, they obviously think they have a lot more centrifuges than U.S. is speaking of--Max
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Tuesday, April 11, 2006 · Last updated 2:46 p.m. PT

Enrichment is only a first step for Iran

By THE ASSOCIATED PRESS

TEHRAN, Iran -- Iran's announcement that it has successfully enriched uranium may be a major breakthrough for its nuclear program, but it's still a long way to being able to fuel a reactor - or produce a weapon, as the U.S. fears.

Iran said it successfully enriched uranium using 164 centrifuges. For large-scale enrichment, Iran needs tens of thousands of centrifuges.

Iran's nuclear boss, Gholamreza Aghazadeh, said Iran aims to expand the process to use 3,000 centrifuges in the last quarter of 2006, meaning Iran is preparing for a semi-industrial scale enrichment.

The centrifuge program is located at the Natanz Uranium Enrichment Plant, parts of which have been built underground to protect it from air or missile strikes.

It is not clear whether reaching the 3,000 mark means building more centrifuges. In 2005 - when Iran had suspended enrichment-related activities - Iranian officials said the country had around 2,000 centrifuges.

Scientists resumed enrichment research at Natanz in February, but Iran has not said whether they have resumed building centrifuges.



Enrichment is a highly difficult process that takes gas produced from raw uranium and aims to increase its proportion of the uranium-235 isotope, needed for nuclear fission.

The gas is pumped into a centrifuge, which spins, causing a small portion of the heavier, more prevalent uranium-238 isotope to drop away. The gas then proceeds to other centrifuges - thousands of them - where the process is repeated, increasing the proportion of uranium-235.

Enrichment typically starts out with a gas that is 0.7 percent uranium-235. It must be boosted to around 4 percent to produce fuel for a reactor - or 90 percent for the material for a warhead.

But getting a series of 164 centrifuges to work is an accomplishment. The same principles can be used to add on more centrifuges - though the more that come on line the more opportunities there are for technical problems.

The pipe connections between the devices is complex and fragile, and any imperfection can cause a breakdown, Iranian nuclear scientist Mohammad Afarideh said.>>