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Episode details

World Service,17 Nov 2018,9 mins

When’s a Kilogram Not a Kilogram?

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Currently there is one kilogram, one kilogram to rule them all, one kilogram in confinement, one kilogram to measure them all and by its mass define them. Sorry…but you get our gist, there is a literal kilogram in a vault in Paris. Only…is it actually a kilogram? That’s what scientists have been questioning for years and why this week they’re voting to change its definition to something altogether more accurate and less tangible that could pave the way for innovation. Presenter/Producer: Lizzy McNeill (The international kilogram prototype, a cylinder of platinum-iridium alloy at the International Bureau of Weights and Measures (BIPM) near Paris / Photo courtesy of BIPM.)

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