Au revoir to the original kilogram: Le Grand K joins the list of relegated metrics
by Gavin Haynes from on (#2XGYK)
The platinum-iridium cylinder used to standardise the kilogram is getting an upgrade - to a complicated process that involves the measuring of light
Time is running out for Hollywood to make its big metrology action thriller. In late 2019, the chance for a leathered-up Jeremy Irons to cut through several thick vaults in Paris suburb Sivres and ransom the world's kilogram will end.
Kept under three bell jars and secured by three keys - only two of which are in France - few objects are as precious to our civilisation as the platinum-iridium cylinder made in 1889 to serve as a new global standard for weighing things. A kilo is a kilo because of this kilo, and it is so precious that it is only taken out once every 40 years - and then only so that replica kilos, kept in other locations, can be compared with it.
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