THE LAST ARTIFACT tells the story of the scientists and metrologists around the world who worked to redefine the kilogram in 2018. The world’s base unit to measure weight, the kilogram was the last of the SI units still defined, not by a universal constant, but by a physical artifact – a man-made cylinder located at the International Bureau of Weights and Measurements in France. The program recounts how a necessary update to the standard resigned this object to history.