As explained in a mailing list post by Jeffrey Sherman, a NIST supervisory physicist who maintains the institute’s atomic clocks, “The atomic ensemble time scale at our Boulder campus has failed due ...

Clocks on Earth are ticking a bit more regularly thanks to NIST-F4, a new atomic clock at the National Institute of Standards and Technology (NIST) campus in Boulder, Colorado. This month, NIST ...

DENVER (KDVR) — It is said that time is relative and passes differently depending on an observer’s relative motion and gravitational potential. Although some would argue time is a construct, it does ...

Ask someone on Earth for the time and they can give you an exact answer, thanks to our planet’s intricate timekeeping system, built with atomic clocks, GPS satellites and high-speed telecommunications ...

What the Clock: Internet time servers are a critical part of the infrastructure used by companies and organizations that rely on atomic clocks to keep accurate time. A US agency responsible for ...

NIST scientists Greg Hoth (left) and Vladislav Gerginov work on NIST-F4, NIST’s new cesium fountain clock. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted ...

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A power outage on Dec. 19 at the National Institute of Standards and Technology (NIST) campus in Boulder, Colo., disrupted operation of the NIST-F4 atomic clock. Hurricane force winds and dry ...

World's first thorium-229 nuclear clock shows potential for ultra-precise timekeeping and fundamental physics tests.

BOULDER • Every second in a small laboratory room in Boulder, a green light flashes. Within the webs of yellow wire and shelves of computer systems, this green light represents the passage of time.