Somewhat interesting that they themselves don't have access to the site. You'd think there would have been some disaster plans put in place?
The failure of a single such server is far from a disaster.
But the stratum 1 time servers can shrug and route around the damage.
And for 99% of that history, Noon was when the sun was half-way through its daily arc at whatever point on Earth one happened to inhabit. The ownership class are the ones who invented things like time zones to stop their trains from running in to each other, and NTP is just the latest and most-pervasive-and-invasive evolution of that same inhuman mindset.
From a privacy point of view, constant NTP requests are right up there alongside weather apps and software telemetry for “things which announce everyone's computers to the global spy apparatus”, feeding the Palantirs of the world to be able to directly locate you as an individual if need be.
In a world where this didn't happen, your comment would most likely read:
> The ownership class are the ones who had such indifference toward the lives of the lower class passengers that they didn't bother stopping their trains from running into each other.
-My Friend Andy
Time services are available from other locations. That's the disaster plan. I'm sure there will be some negative consequences from this downtime, especially if all the Boulder reference time sources lose power, but disaster plans mitigate negative consequences, they can't eliminate them.
Utility power fails, automatic transfer switches fail, backup generators fail, building fires happen, etc. Sometimes the system has to be shut down.
Remember - the Marshall fire started on December 30, 2021 under similar high wind conditions. [2] 1,000 structures destroyed, two deaths.
There's no present need for important hard-to-replace sciencey-dudes to go into the shop (which is probably both cold, and dark, and may have other problems that make it unsafe: it's deliberately closed) to futz around with the the time machines.
We still have other NTP clocks. Spooky-accurate clocks that the public can get to, even, like just up the road at NIST in Fort Collins (where WWVB lives, and which is currently up), and in Maryland.
This is just one set.
And beyond that, we've also got clocks in GPS satellites orbiting, and a whole world of low-stratum NTP servers that distribute that time on the network. (I have one such GPS-backed NTP server on the shelf behind me; there's not much to it.)
And the orbital GPS clocks are controlled by the US Navy, not NIST.
So there's redundancy in distribution, and also control, and some of the clocks aren't even on the Earth.
Some people may be bit by this if their systems rely on only one NTP server, or only on the subset of them that are down.
And if we're following section 3.2 of RFC 8633 and using multiple diverse NTP sources for our important stuff, then this event (while certainly interesting!) is not presently an issue at all.
Fun facts about The clock:
You can't put anything in the room or take anything out. That's how sensitive the clock is.
The room is just filled with asbestos.
The actual port for the actual clock, the little metal thingy that is going buzz, buzz, buzz with voltage every second on the dot? Yeah, that little port isn't actually hooked up to anything, as again, it's so sensitive (impedance matching). So they use the other ports on the card for actual data transfer to the rest of the world. They do the adjustments so it's all fine in the end. But you have to define something as the second, and that little unused port is it.
You can take a few pictures in the cramped little room, but you can't linger, as again, just your extra mass and gravity affects things fairly quickly.
If there are more questions about time and timekeeping in general, go ahead and ask, though I'll probably get back to them a bit later today.
Unfortunately, the HP cesium clock that backed the utcnist systems failed a few weeks ago, so they're offline. I believe the plan is to decommission those servers anyway - NIST doesn't even list them on the NTP status page anymore, and Judah Levine has retired (though he still comes in frequently). Judah told me in the past that the typical plan in this situation is that you reference a spare HP clock with the clock at NIST, then drive it over to JILA backed by some sort of battery and put it in the rack, then send in the broken one for refurb (~$20k-$40k; new box is closer to $75k). The same is true for the WWVB station, should its clocks fail.
There is fiber that connects NIST to CU (it's part of the BRAN - Boulder Research and Administration Network). Typically that's used when comparing some of the new clocks at JILA (like Jun Ye's strontium clock) to NIST's reference. Fun fact: Some years back the group was noticing loss due to the fiber couplers in various closets between JILA & NIST... so they went to the closets and directly spliced the fibers to each other. It's now one single strand of fiber between JILA & NIST Boulder.
That fiber wasn't connected to the clock that backed utcnist though. utcnist's clock was a commercial cesium clock box from HP that was also fed by GPS. This setup was not particularly sensitive to people being in the room or anything.
Another fun fact: utcnist3 was an FPGA developed in-house to respond to NTP traffic. Super cool project, though I didn't have anything to do with it, haha.
Now if the (otherwise very kind) guy in charge of the Bureau international des poids et mesures at Sèvres who did not let me have a look at the refrerence for the kilogram and meter could change his mind, I would appreciate. For a physicist this is kinda like a cathedral.
They have so many incredible artifacts (for weights and measures but also so much more: engineering, physics, civil engineering, machining,...)
I spent 4 hours to there and was surprised to see so many tourists, this is not a place I expected people visiting Paris to go to. There were no crowds though.
The top part is really great, you get to see how much people did with so little. So is the chemistry part.
I found the steel replica of the kilogramme and the meter, and of course the Foucault pendulum (in the neighboring refurbished church).
This is truly an interesting museum, on part with the museum of discoveries (musée de la découverte) which is unfortunately close now for a few years for renovations (or at lest was recently planned to be closed). Much better than La Vilette.
So thank you again!
The Musée de Sèvres (or Bureau des Mesures as it is called now) has the original kilogramme and meter iridium reference, hidden in the basement ;( So if the director has a change of heart, I am all in!
Can you restate this part in full technical jargon along with more detail? I'm having a hard time following it
but yes, I also want the juicy details!
so this is the clock
https://en.wikipedia.org/wiki/NIST-F1
or this
https://en.wikipedia.org/wiki/NIST-F2
or there's already F4 too, but it doesn't have a Wikipedia article yet
https://www.nist.gov/news-events/news/2025/04/new-atomic-fou...
but maybe they are talking about the new non-microwave clocks that use Ytterbium-based optical combs ...
or about the Aluminum ion clock
https://www.nist.gov/news-events/news/2025/07/nist-ion-clock...
mind blown
https://www.nist.gov/pml/time-and-frequency-division/time-re...
and you can see a photo of the actual installation here:
https://www.denver7.com/news/front-range/boulder/new-atomic-...
As you can see, the room is clearly not filled with asbestos. Furthermore, the claim is absurd on its face. Asbestos was banned in the U.S. in March 2024 [1] and the clock was commissioned in May 2025.
The rest of the claims are equally questionable. For example:
> The actual port for the actual clock ... isn't actually hooked up to anything ... they use the other ports on the card for actual data transfer
It's hard to make heads or tails of this, but if you read the technical description of the clock you will see that by the time you get to anything in the system that could reasonably be described as a "card" with "ports" you are so far from the business end of the clock that nothing you do could plausibly have an impact on its operation.
> You can't put anything in the room or take anything out. That's how sensitive the clock is.
This claim is also easily debunked using the formula for gravitational time dilation [2]. The accuracy of the clock is ~10^-16. Calculating the mass of an object 1m away from the clock that would produce this effect is left as an exercise, but it's a lot more than the mass of a human. To get a rough idea, the relativistic time dilation on the surface of the earth is <100 μs/day [3]. That is huge by atomic clock standards, but that is the result of 10^24kg of mass. A human is 20 orders of magnitude lighter.
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[1] https://www.mesotheliomahope.com/legal/legislation/asbestos-...
[2] https://en.wikipedia.org/wiki/Gravitational_time_dilation
I thought it was US Space Force / Air Force. Was the Navy previously or currently involved?
In this context, they feed timing updates to the GPS operators https://www.cnmoc.usff.navy.mil/Our-Commands/United-States-N...
Either go with one clock in your NTPd/Chrony configuration, or ≥4.
Yes, if you have 3 they can triangulate, but if one goes offline now you have 2 with no tie-breaker. If you have (at least) 4 servers, then one can go away and triangulation / sanity-checking can still occur with the 3 remaining.