Researchers Will Consider a New World Kilogram Standard

In a lab­o­ra­to­ry vault out­side Paris is a small cylin­der of plat­inum – irid­i­um alloy that serves as the stan­dard for all mass mea­sure­ments world­wide. By an 1889 inter­na­tion­al accord, the mass of this met­al cylin­der defines the kilogram.

…

The ref­er­ence cylinder’s mass has drift­ed slight­ly through the years — not enough to throw off your bath­room scale, but enough to both­er mea­sure­ment scientists.

Researchers plan to dis­cuss relat­ing the kilo­gram to Planck’s con­stant.

01/24/2011 8:41 pm