It's also a little surprising when you think about it. Look how far science has come despite a very shaky foundation in the system of measurements. I'm sure mo

It's also a little surprising when you think about it. Look how far science has come despite a very shaky foundation in the system of measurements. I'm sure most people know, but the mass of the official kilo actually drifted by tens of micrograms since it was made. When you're talking about very large weights, that can be an enormous difference!