Inside Nuclear Reactors

Benign Name, Nasty Stuff
Iranian technicians in Isfahan feed yellowcake into a barrel before processing it into fuel in August 2005. Remember yellowcake, the concentrated uranium powder former President George W. Bush erroneously insisted Saddam Hussein was hoarding to build weapons of mass destruction? The claim may have been false, but the powder is very real — and it's not just the good guys who have it.

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