For decades, metrologists have strived to retire ‘Le Grand K’ — the platinum and iridium cylinder that for 126 years has defined the kilogram from a high-security vault outside Paris. Now it looks as ...

Add Yahoo as a preferred source to see more of our stories on Google. Le kilogramme est mort. Vive le kilogramme! The U.S. National Institute of Standards and Technology called this Friday a “turning ...

The NIST-4 Kibble balance, an electromagnetic weighing machine that is used to measure Planck's constant, and in turn, redefine the kilogram. Jennifer Lauren Lee / NIST Locked in a vault that requires ...

The International Committee for Weights and Measures is about to reach a decision that could affect the teaching and understanding of basic science for the next hundred years. It has passed a ...

The official definition of a kilogram has been changing for well over a century, but this week it may be redefined for the final time. After years of debate and discussion, scientists from around the ...

It may not change how you buy bananas, but scientists have voted to redefine the value of a kilogram, in what they called a landmark decision that will boost the accuracy of scientific measurements.