Scientists and policy makers from around 60 nations voted unanimously Friday to redefine the kilogram. The decision at the General Conference on Weights and Measures in Versailles, France was greeted ...

For nearly 130 years, the kilogram has been defined by a small platinum and iridium cylinder sitting in a vault outside Paris. Every other unit of measurement is defined by reproducible physical ...

Physicists in the US say that they have used publicly available data from global positioning system (GPS) satellites to put a limit on how much Planck’s constant might vary from place to place. Their ...

A high-tech version of an old-fashioned balance scale at the National Institute of Standards and Technology (NIST) has just brought scientists a critical step closer toward a new and improved ...

The remarkable thing about our universe is that it’s possible to explore at least some of its inner workings with very simple tools. Gravity is one example, to which [Galileo]’s inclined planes and ...

Planck’s constant is one of the most important numbers in science. It describes the relationship between the energy and frequency of an electromagnetic wave in an equation known as the Planck-Einstein ...

Deep underneath the Parisian suburb of Saint-Cloud, in a vault that can only be opened by three people wielding three different keys, there lies a hunk of metal that is so crucial to the world of ...

What does a kilogram weigh? Middle school science classes often teach that the unit is based on the weight of water—specifically a cube of water, a tenth of a meter on each side, at just above ...

Editor’s Note: If you haven’t watched season 3 of “Stranger Things” and don’t want to be spoiled, stop reading! Season 3 of Netflix’s “Stranger Things” expresses a subtle appreciation of science and ...