Tag Archives: le grand k

Goodbye, My Sweet, Sweet Kilogram

So today is a historic day. Why? The kilogram has been officially re-defined to be based on a fundamental constant of nature rather than a physical object.

Since 1889, our bro the kilogram had been defined by “Le Grand K,” a small platinum alloy object that was kept as isolated as possible (to try to avoid any increase/decrease in its mass) and was THE definition of the kilogram. Whatever Le Grand K weighed, it equaled a kilogram.

And up until today, the kilogram was the last of the SI base units to be defined by a physical object rather than a fundamental constant. But that all changed today when the International System of Units officially changed the definition of the kilogram to be in terms of the Planck constant.

Y’all might be like who gives a poop, but this is seriously cool and historic news. We redefined a basic unit of measurement today. How often does that happen? The last time we did it was in 1960 with the meter. Now the kilogram is actually constant and is not in flux with the minute changes that take place with a physical object.

NNNNNF THAT’S JUST FREAKING COOL I LOVE THIS KIND OF STUFF

It’s also kinda sad. The uniqueness of the kilogram always made me happy and made it my favorite of the base SI units. It still is my favorite, though, ‘cause of its history.

Anyway.

(Yes, I’m fangirling over an SI unit, what’re you gonna do about it?)

 

 

 

HEAVY NEWS

It’s official! The definition of the kilogram (and a few other units) is being changed next May. Specifically, our buddy the kilogram will now be defined using the Planck constant as opposed to Le Grand K, the physical object that has been the kilogram since forever.

Very cool. Kinda sad, though. The kilogram will still be my favorite SI base unit, even though some of its uniqueness is being stripped away for more precision. Not that that’s a bad thing, but still…