NIST – National Institute of Standards and Technology

NIST (National Institute of Standards and Technology) is a U.S. federal agency responsible for developing measurement standards, advancing metrology, and promoting innovation through science and technology. It maintains primary standards for time and frequency and contributes to the realization and dissemination of Coordinated Universal Time (UTC).

In geodesy, NIST plays an important role by providing highly stable atomic time and frequency standards that underpin space-geodetic techniques such as GNSS and VLBI. Precise timing is essential for accurate positioning, satellite orbit determination, Earth rotation measurements, and the realization of global geodetic reference frames.

More info: https://www.nist.gov/