How a power outage in Colorado caused U.S. official time to be 4.8 microseconds off

https://www.npr.org/2025/12/21/nx-s1-5651317/colorado-us-official-time-microseconds-nist-clocks
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How a power outage in Colorado caused U.S. official time to be 4.8 microseconds off

A power outage and subsequent generator failure at the National Institute of Standards and Technology (NIST) lab in Boulder, Colorado, caused the U.S. official time to be delayed by 4.8 microseconds. While imperceptible to the general public, this minute drift could have implications for critical infrastructure, telecommunications, and GPS signals, prompting NIST to notify high-end users of the disruption.

Note

that sounds like a stressful 4.8ms

Published

2025

Summary

A power outage and subsequent generator failure at the National Institute of Standards and Technology (NIST) lab in Boulder, Colorado, caused the U.S. official time to be delayed by 4.8 microseconds. While imperceptible to the general public, this minute drift could have implications for critical infrastructure, telecommunications, and GPS signals, prompting NIST to notify high-end users of the disruption.

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