3 ms·
More about that piece of platinum in Paris, the International Prototype Kilogram (IPK): https://en.wikipedia.org/wiki/Kilogram#International_prototype_kilogram
by aftbit 10y ago
More about that piece of platinum in Paris, the International Prototype Kilogram (IPK): https://en.wikipedia.org/wiki/Kilogram#International_prototype_kilogram https://en.wikipedia.org/wiki/Kilogram#International_prototy...
Also, something I had never heard of, Vienna Standard Mean Ocean Water: https://en.wikipedia.org/wiki/Vienna_Standard_Mean_Ocean_Water https://en.wikipedia.org/wiki/Vienna_Standard_Mean_Ocean_Wat...