A Very Round Object Helps Build a Better Mass Measurement
Right now, the U.S. and Germany have different approaches to defining, or “realizing” as the researchers call it, the kilogram. Here, NIST researcher Darine Haddad looks on as German researcher Beatrice Rodiek places a sphere on NIST’s highly accurate weighing machine, known as the Kibble balance. The goal of the research is to get closer to the same definition using the different methods. Credit: B. Hayes/NIST
In 2018, the world agreed to redefine the kilogram.