The kilogram may finally get a break from its yo-yo diet. An international team of scientists is closer to redefining the unit of mass based on fundamental constants, instead of a piece of metal in France that loses weight only to put it back on again.
Since 1889, the international standard for the kilogram has been a cylinder of platinum, tucked under a glass jar inside another glass jar, stored in a vault outside Paris.
Log in
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.