Did Stuxnet Take Out 1 , 000 Centrifuges at the Natanz Enrichment Plant ?

Although mechanical failures or operational problems have often been discussed as causing problems in the IR-1 centrifuges, the crashing of such a large number of centrifuges over a relatively short period of time could have resulted from an infection of the Stuxnet malware. This malicious code seeks to take over an industrial control system in order to destroy equipment while hiding its presence. Given Stuxnet’s much greater prevalence in Iran compared to other countries, it is likely that this malware was aimed at Iran. Stuxnet covertly changes the frequencies of certain types of frequency converters, which control the speed of motors. The frequencies listed in Stuxnet’s attack sequences, including the nominal frequency of a motor, imply that a target is the IR-1 centrifuge. However, Stuxnet’s exact purpose or its overall effect on the FEP remains hard to assess. If Stuxnet’s goal was the destruction of all the centrifuges in the FEP, Stuxnet failed. But if its goal was to destroy a more limited number of centrifuges and set back Iran’s progress in operating FEP while making detection of the malware difficult, it may have succeeded, at least for a while.