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NIST was 5 μs off UTC after last week's power cut - Jeff Geerling
If you were 5 microseconds late today, blame it on NIST. Their facility in Boulder Colorado just had its power cut for multiple days. After a backup generator failed, their main ensemble clock lost track of UTC, or Universal Time Coordinated. But even if you used the NTP timing servers they run, they were never off by more than 5 microseconds. 5 μs might seem insignificant. But it is significant for scientists and universities who rely on NIST's more specialized timing signals.