I know this wasn't meant literally, but it does make for an interesting thought experiment - under what circumstances might it be valid to dial 911 to ask for the time?

My first thought was something like a nuclear operator - "we need to shut down the core at exactly 19:00, but our clocks are down!" so they call and wait for the operator to advise when the time is reached. Obviously contrived and not realistic, but interesting to think about.

That's what the US Naval Observatory Master Clock phone service is for: 719-567-6742

> under what circumstances might it be valid to dial 911 to ask for the time?

Maybe, if all of your clocks don't work and you went to somewhere else and their clock isn't working either, and it is raining and you cannot use a sundial, and you tried to call everyone else already and they also cannot give you the time for whatever reason, then you might try to call 911 and ask them, because you tried everything else and it didn't work. (I once heard a (fictional) story where this happened. This is an unlikely scenario, but some of the things mentioned here (and other things) might happen, e.g. bad weather so you cannot go out, the television and computers are not working (and maybe the power is out but the telephone uses a separate power), and there are some problems with the telephone too (I have had problems before where some telephone numbers worked and some didn't), etc.)

Well given that virtually everyone's "telephones" are cell phones which would be incapable of making calls unless they connected to the network, and the network would be incapable of handling their calls without also telling the phone what time it is, this situation becomes far less tenable in 2025 vs the 20th century when land lines were king. :)

In the UK they are fine with you calling 999 to test your newly-configured office phone routing. They don't want a chat though.

That's a bit different than asking for the time. That's testing a newly configured emergency system to make sure it works.

At least in many European countries, the landline phone companies offered a short number for obtaining the time from an answering robot.

Many, many years ago, I have designed a piece of equipment that was integrated in a phone exchange and it provided vocal messages to be sent to a caller, for errors like non-existent phone number, but also for replying to the dedicated number for the time service. The messages were something like "The time at the next beep will be ... hours ... minutes ... seconds".

I have not heard about a similar service for mobile phones, because here the phone gets the time automatically and it displays it.

It's not a good idea to call 911 with non-emergencies.

But until a few decades ago, the primary way most of us to set our clocks was to call a number the phone company provided, which in our case was TI4-1212. "At the tone, the time will be ..."

You can still call NIST and get the time via "at the tone...": https://www.nist.gov/pml/time-and-frequency-division/time-di...

If a response packet contains a good timestamp, you could initiate a 911 call, get a reply packet, and cancel the call before it reaches any actual operators.