Ms Katie Green holding a conical polishing tool. In front of her is a bench with a basin sunk into it. In the centre of the basin is a grey sphere mounted on a spindle .

Ms Katie Green about to start polishing a silicon sphere.

Making the perfect kilogram

Discover CSIRO’s role in creating a perfect sphere that may one day redefine the kilogram as discussed in this podcast by Ms Katie Green from CSIRO’s Australian Centre for Precision Optics. (5:37)

  • 18 June 2007 | Updated 7 March 2012

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Australian scientists and optical engineers have taken up the challenge of turning a silicon cylinder into the perfect one kilogram sphere.

At the moment, the kilogram is defined by a metal cylinder in a vault in France.

Now, the decision has been made to create a new kilogram standard using exceptionally pure silicon.

CSIRO’s Australian Centre for Precision Optics (ACPO) will work with Australia’s National Measurement Institute to create the sphere.

In this podcast, Optical Engineer Ms Katie Green describes what it will take to create the new kilogram standard.

Read more about Precision spheres in push to re-define kilogram.