The kilogram isn't a thing anymore. Instead, it's an abstract idea about light and energy. As of today (May 20), physicists have replaced the old kilogram — a 130-year-old, platinum-iridium cylinder ...

Left: Antarctic ice core and the bubbles contained in it. Right: Vacuum-ultraviolet light source and metastable krypton atom beam device. A team led by Prof. Zheng-Tian Lu and Prof. Wei Jiang from the ...

For more than a century, a single metal cylinder in a Paris vault quietly defined what a kilogram was. After 130 years, scientists deliberately killed that object’s authority and rebuilt the standard ...

The kilogram is losing weight and many scientists agree that it's time to redefine it. They are hoping to redefine the kilogram by basing it on standards of universal constants rather than on an ...

Grams (g) and kilograms (kg) are used to describe measurements of mass. Grams are used for smaller or lighter items. 1,000 grams are equal to 1 kilogram. You can write it like this: 1,000 grams = 1 ...