Comment by tekne
8 hours ago
What deeply confuses me is why we don’t just:
- always use atomic time
- adjust civil timezones as needed to match astronomical time well enough
Somehow, I don’t see most political and contingent timezones lasting long enough to shift by an hour…
That's an interesting idea, but it could be argued that this assumes that all of the world's timezones will agree to observe the same set of leap seconds as they currently do.
Otherwise, it shifts timezones from being 15 minute granularity to 1 second granularity. Not technically impossible, but will definitely make cross-boarder meetings interesting once the discrepancy becomes large enough. I feel the 15 and 30 minute timezones are already bad enough.
Leapseconds don't track solar time particularly well-- they track a 'mean time' (because there are large periodic variations!) which you can't even directly observe-- across the year the span is about 30 minutes.
If you have an application that needs a precise solar/astronomical time, you need to back out the leap seconds and then apply a more accurate correction already.
Because of this, I think it would be completely reasonable to just move timezones by 1 hour once the adjustment would be an improvement in accuracy--- which I seem to recall can be estimated to take about 4500 years. The adjustment is already compatible with existing software, and infrequent planned changes of this sort already happen for political reasons.
It won't hurt most usages, it will greatly help computer and recordkeeping usage, and precise solar/astronomical time will also be derisked due to fewer snafus with backing out leapsecond or incorrectly applying them.
The issue will become more critical as we deploy more timing sensitive distributed systems, and especially a low cost atomic timekeeping improves.
It seems likely me that some optical clock designed could eventually be miniaturized and give e.g. 1 second per 32 years drift performance (1ppb-- which is what commercially available miniature atomic clocks can already do) in an affordable and power efficient device. Then you could have correction/communication-free time to 'conventional precision'. But if an unpredictable feed of leap seconds is required you can never have that.
Because then one day you wake up early in the morning to find the noonday sun staring at you. It will take a while though. On second [heh] thought, you might not wake up. But some distant relative would.