At a gathering in France, the scientific community agreed to redefine the definition of a kilogram.
“The vote is a unanimous yes, I hope that such votes will be possible for many other issues in the world,” said professor Sebastien Candel, president of the French Academy of Sciences.
To clarify, the definition of a kilogram has been listed as the exact weight of an actual piece of metal called “Le Grand K’ since 1889.
Yet scientists have been aware of a growing problem with Le Grand K. Despite being protected by glass bell jars and securely held within the International Bureau of Weights and Measures in Sèvres, France, the standard has been slowly losing mass. By 2018, Le Grand K had lost 50 micrograms resulting in it becoming only 99.999995 of its original mass. While not significant to the average person, this difference would wreak endless havoc on precise measurements.
To resolve the issue scientists gathered at the General Conference on Weights and Measures an unanimously voted to retire Le Grand K in favor of the unchanging mathematical concept – Planck’s constant. Planck’s constant is one of the smallest measures possible at (6.62607004 × 10-34 m2 kg / s).
This is not the first measurement to be redefined. In 1791, the French Academy of Sciences declared that a meter was 1/10 millionth of the distance from the North Pole to the equator of a line running through Paris. In 1889, the same year Le Grand K was cast, the International Bureau of Weights and Measures created a bar of platinum and iridium alloy with two lines on it that were exactly one meter apart. In 1960 the wavelengths of the spectrum in a krypton-86 atom were used to define a meter, and in 1983 scientists finally decided to settle on defining it as the distance light could travel in a vacuum in 1/299,792,458 second.
