The kilogram gets new definition!
In an historic vote, nations unanimously approved Friday a ground-breaking overhaul to the international system of measurements, creating new definitions for the kilogram and other key units vital for trade and science. Scientists for whom the update represents decades of work clapped, cheered and even wept as the 50-plus nations one by one said “yes” or “oui” to the update. Nobel prize winner William Phillips said now, it can be certain, “that the kilogram is stable.” He added, “we weren’t sure of that in the past. And now we will be.” The so-called “Grand K” kilogram, a cylinder of polished platinum-iridium alloy that has been the world’s sole true kilo since 1889, is to be retired.