An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
After two years of difficult and meticulous work examining, refurbishing, and testing the aging workhorse watt balance called NIST-3, PML researchers have used
Note:
Much more recent information is available about redefinition of the SI units. For a comprehensive general overview, see How to Weigh Everything from
Every day is a metric day at the National Institute of Standards and Technology (NIST). But that won't stop the agency from celebrating Metric Week, held