Wowsers.

https://groups.google.com/a/list.nist.gov/g/internet-time-service/c/o0dDDcr1a8I

“In short, the atomic ensemble time scale at our Boulder campus has failed due to a prolonged utility power outage. One impact is that the Boulder Internet Time Services no longer have an accurate time reference. At time of writing the Boulder servers are still available due a standby power generator, but I will attempt to disable them to avoid disseminating incorrect time.”

…

“we now have strong evidence one of the crucial generators has failed. In the downstream path is the primary signal distribution chain, including to the Boulder Internet Time Service”

(I’ve met Jeff Sherman, who indeed works at NIST)

I guess Xcel Energy didn't give NIST much notice about this Public Safety Power Shutoff either. I'm surprised they couldn't keep them powered. The power shutoff is supposed to prevent wildfires due to high winds/downed lines between the cities, but NIST is in Boulder proper.

https://www.cbsnews.com/colorado/news/power-outage-boulder-atomic-clock-nist/

“As a result of that lapse, NIST UTC drifted by about 4 microseconds”

Usually their error with respect to the BIPM is measured in nanoseconds. If GPS had this error, positioning uncertainty would be more than a kilometer.

Before I retired, there was a meeting with NIST folks about them looking at USNO’s power backup systems, because they wanted to upgrade. Looks like that didn’t happen, but the problem is finding the money. Beancounters don’t always appreciate the importance, and everybody is making their case, so someone else (probably without technical expertise) decides what the priorities are.

This would be a very unsatisfying “We told you so.” The blame game might get ugly.

2 hours ago, swansont said:

https://www.cbsnews.com/colorado/news/power-outage-boulder-atomic-clock-nist/

“As a result of that lapse, NIST UTC drifted by about 4 microseconds”

Usually their error with respect to the BIPM is measured in nanoseconds. If GPS had this error, positioning uncertainty would be more than a kilometer.

Before I retired, there was a meeting with NIST folks about them looking at USNO’s power backup systems, because they wanted to upgrade. Looks like that didn’t happen, but the problem is finding the money. Beancounters don’t always appreciate the importance, and everybody is making their case, so someone else (probably without technical expertise) decides what the priorities are.

This would be a very unsatisfying “We told you so.” The blame game might get ugly.

Is USNO-calibrated time just for GPS and military stuff? I presume NIST-calibrated time is what world commerce and everything else runs on? Are the two systems usually in unison i.e. within nanoseconds/microseconds of each other?

Edited Sunday at 05:15 PM2 days by StringJunky

51 minutes ago, StringJunky said:

Is USNO-calibrated time just for GPS and military stuff? I presume NIST-calibrated time is what world commerce and everything else runs on? Are the two systems usually in unison i.e. within nanoseconds/microseconds of each other?

GPS time is UTC(USNO) and is used a lot of places, so while the mandate is for DoD, it leaks into a lot of places. There’s a memorandum of understanding that NIST and USNO time agree to some level (IIRC it’s under 100 ns but usually are within 10 ns or so) and they both steer to agree with the international standard, BIPM.