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Time & frequency
Overview
Time and frequency activities at NIST include maintaining standards, providing official time to the U.S., and carrying out a broad program of research and service activities in time and frequency metrology.
The Research
Additional Resources Links
What Is Time?
Philosophically, what is "time"? Even if we don’t completely understand what time is, we can precisely measure what time it is, thanks to the atomic clock, humankind’s most accurate measurement device. Atomic clocks have revolutionized navigation. Only time will tell us its future applications.
Running Out of Time
In their second suspenseful adventure, the League of SI Superheroes battles archvillain Major Uncertainty in a race to keep the world's satellite navigation system "on time".
News
Keeping Time at NIST
NIST-Designed Photonic Chip Transforms a Single Beam of Light Into Multiple Beams, Each With a Panoply of Different Properties
Jun Ye: A Timely Profile
