:: Re: [DNG] Timezones: Was: Your comp…
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Auteur: Simon Hobson
Date:  
À: dng
Sujet: Re: [DNG] Timezones: Was: Your computer clock: Was:Re: vdev
Hendrik Boom <hendrik@???> wrote:

> On Wed, Aug 10, 2016 at 10:59:07AM +0100, Simon Hobson wrote:
>> Err, no it isn't - unless you've found the secret of time travel ! You're a day ahead of us.
>>
>> Your clock says 11th Aug, in the rest of the world it's still the 10th Aug. And from your message headers :
>
> Might he live just west of the International Date Line?


Two reasons why that wouldn't explain it.

Firstly, he gives the time as CEST (UTC+2h)
Secondly, at the time I wrote the email, which was some time after he'd sent his, he'd be just coming up to midnight if he was in that very small list of places in the UTC+14 timezone - eg Kiritimati, Christmas Island, Kiribati, Samoa with DST
http://www.timeanddate.com/worldclock/kiribati/kiritimati

So while I was at the time unaware (or had forgotten) about those select UTC+14 places, I was correct in saying that the rest of the world was still on 10th and that would still be correct for another 53 seconds after I sent the message :-)

Incidentally, the stories behind some of these bits of trivia can be fascinating. I vaguely recall some islands shifting by a day - ie declaring them to now be in a UTC+nn timezone instead of UTC-nn. I suspect the "we are first to see in the new year" (and hence get a bit of tourist trade) factor may have been involved, but I vaguely recall it was more a case of them having more affinity with the Russia/China/Australia part of the world (and all the islands in that expanse of ocean) than with America - and thus it making sense to be in the same day as those (to us) eastern countries.

Ah, I stand corrected, according to https://en.wikipedia.org/wiki/UTC%2B14:00 it was because parts of the colony were on different sides of the IDL and that meant that they only had 4 working days in common - Monday on one island would be Sunday on another, and similarly with Friday/Saturday (in the reverse direction).

For good measure, Australia has 1/2 hour offsets in some of it's time zones (and even one with a 1/4 hour offset !) - which I would have thought must cause "a certain amount of confusion"
http://www.timeanddate.com/time/australia/time-zones-background.html

I guess some of these oddities had their reasons at the time - the UK used to have local times which varied across the country, it was only the expansion of the railways that made a common timezone "useful". And since then, there's probably a "that's our history, you can't change it" response to any suggestions of rationalisation !

As I say, can be fascinating - and a welcome diversion from work ;-)