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 ...

It’s time to replace the 115-year-old kilogram artifact as the world's official standard for mass, even though experiments generally thought necessary to achieve this goal have not yet reached their ...

The definition of a kilogram, a unit roughly equal to 2.2 pounds, has changed forever. Since 1889, the kilogram has been defined by a platinum-iridium alloy cylinder nicknamed Le Grand K, which is ...

How much is a kilogram? It turns out that nobody can say for sure, at least not in a way that won’t change ever so slightly over time. The official kilogram – a cylinder cast 118 years ago from ...

SEVRES, France — The kilogram is getting an update. No, your bathroom scales won’t suddenly become kinder and a kilo of fruit will still weigh a kilo. But the way scientists define the exact mass of a ...

The kilogram is getting an update. No, your bathroom scales won’t suddenly become kinder and a kilo of fruit will still weigh a kilo. But the way scientists define the exact mass of a kilogram is ...

Recent studies have shown that the kilogram may need to go on a diet because it has gained tens of micrograms of mass from surface contamination. Recent studies have shown that the kilogram may need ...

After a fraught few years, experiments to redefine the unit have reached agreement. For decades, metrologists have strived to retire ‘Le Grand K’ — the platinum and iridium cylinder that for 126 years ...