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World's Roundest Object
The world's roundest object helps solve the longest running problem in measurement - how to define the kilogram.
The Avogadro project aims to redefine Avogadro's constant (currently defined by the kilogram -- the number of atoms in 12 g of carbon-12) and reverse the relationship so that the kilogram is precisely specified by Avogadro's constant. This method required creating the most perfect sphere on Earth. It is made out of a single crystal of silicon 28 atoms. By carefully measuring the diameter, the volume can be precisely specified. Since the atom spacing of silicon is well known, the number of atoms in a sphere can be accurately calculated. This allows for a very precise determination of Avogadro's constant.
HoldingAccount
I imagine our American friends going: "I reckon that's about two pounds"
TommyToranger
I read avocado
MerToo
It's actually the world's flattest object, viewed through a fisheye lens. Nice try, trick photographers!
throughthoughtthough
Nice try sheeple http://www.theflatearthsociety.org/cms/
keyserv
Yes, sciencey words.
ButtholeIceCreamParlor
Don't go in the sphere.
TheNextBestUsername
How did they verify its roundness?
IMissYourMusk
Magnets
DoubleChungTransplant
A roundometer
groundginger
Actually good question
HeroThatWasNeeded
Scientifically
THEfreshestbrew
They rolled it down a hill
chrismofer
a laser meter measures with incredible resolution.
weaslor
Wrong! It's too shiny, the laser would just bounce everywhere. Proof: my laser mouse doesn't work on a mirror.
chrismofer
wut
TheLimpinBiscuit
Isn't a kilogram just a thousand grams? What's so hard about that?
MerToo
Easy! And a gram is a thousand milligrams, at which point we just need a Reference Milligram on which all other wights can be based!
buenoisawesome
I think they are trying to have as close to a perfect kilogram as possible, so that they can define Avogadro's number as closely as possible