Weighty matters: a platinum-iridium kilogram belonging to the US National Institute of standards and Technology. (Courtesy: J.L. Lee/NIST) Metrologists and policy-makers from 60 countries around the ...

Brian Resnick was Vox’s science and health editor and is the co-creator of Unexplainable, Vox’s podcast about unanswered questions in science. Forty feet underground in Gaithersburg, Maryland, in a ...

A flaw in the system leaves physicists grappling with dimensionless units. Water is a precious resource. So protest erupted when, last September, India’s Supreme Court ordered Karnataka state to ...

A new definition of the kilogram is required, an international team of scientists contends. The current one is imprecise, they say, because it is not linked to an unvarying property of nature. The ...

New research, published by the National Physical Laboratory (NPL), takes a significant step towards changing the international definition of the kilogram – which is currently based on a lump of ...