Perfect Silicon Sphere to Redefine the Kilogram

MrCreosote writes "The Age reports optical specialists at CSIRO are helping create a new standard for the kilogram, based on a precise number of atoms in a perfect sphere of silicon. This will replace the International Prototype, a lump of metal alloy in a vault in Paris."

Comments

Ah yes...

[Nerdposeur]

..but how can they make sure the new kilogram weighs a kilogram? :)

Re:"perfect" sphere

[Anonymous Coward]

>May God have mercy on your soul if you ever attempt to call a woman a physical object to her face.
Especially if he compares her to a perfect sphere.

Re:"perfect" sphere

[CommunistHamster]

It makes the calculations simpler.

perfect, well-rounded, bouncy

[siddesu]

silicon spheres will define the standard ... will they be coming in pairs by any chance?

SI horsepower

[Bromskloss]

One horsepower is the power of the reference horse in an archive in Paris.

Exam

[matt me]

Weird. I read about this in an exam I took last week. It stated that the present standard kilogram is a mass of platinum and iridium kept at STP underground, and asked what factors might affect the mass of the standard kilogram when it is measured. I answered if any isotopes of platinum or iridium decay, or if the standard kilogram had a velocity close to the speed of light.

Re:alternate theories

[hanshotfirst]

Duck Measurer: "I put a duck on one side of the scale, and use weights (lumps of known mass) on the other side to determine the mass of the duck."
Some Guy: "Umm, but you already know the mass of the weights, why are you bothering?"

To see if they float, of course.