Latest Watt balance Stories
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 platinum-iridium kept in Paris.
Scientists are close to establishing a non-physical definition of the kilogram--the last remaining base unit in the International System of Units (SI) still defined by an existing object--after it was revealed that the prototype used to establish the measurement is shrinking.
Taking the first steps of what would be a major historical advance in the science of measurement, the National Institute of Standards and Technology (NIST) is participating in a worldwide effort to recommend major revisions to the International System of Units (SI), the modern metric system that is the basis of global measurements in commerce, science and other aspects of everyday life.
The kilogram is losing weight and many international scientists, including some at Sandia National Laboratories, agree that itâ€™s time to redefine it.