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Australia/Lord_Howe is the weirdest timezone

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Re: Australia/Lord_Howe is the weirdest timezone

#202

Nah, the weirdest time zone is Africa/Addis_Ababa, which nobody in Ethiopia follows. Instead the locals offset the time by 6 hours. So the AM cycle starts at dawn (i.e. 6am), and the PM cycle starts at dusk (i.e. 6pm). https://en.wikipedia.org/wiki/Time_in_Ethiopia

This is common across East Africa, including Kenya where I’m from. The night ends at 6:00AM, with 7:00AM being saa moja (first hour) of the day. Similarly, the day ends at 6:00PM (thenashara). Intuitively, this clock makes much more sense than the English clock. There’s rarely confusion between times because it’s embedded in the language.

This is indeed a more logical clock, as it follows the natural cycle of activity. Equally, calendars that put the end of the year at the time after harvest ("autumn"), or at the start of agricultural work ("spring") are also more logical.

Positioning the beginning of a new day at noon, and a new year t a solstice, is just a technical convenience, because these are easy to detect with very simple astronomy tools.

Re: Australia/Lord_Howe is the weirdest timezone

#203

I kind of thing a half hour daylight savings difference instead of an hour is a pretty low bar for the weirdest timezone. Almost any of the others are weirder: Antarctica/Troll definitely sounds weirder. The Moroccan and Gazan timezones that can't be expressed by the system as it was written because at least that means that they have some different kind of a rule, even if lunar time is well known. Same with the ones…

Leap seconds are generally trivia, but they become absolutely crucial in applications where multiple parties must be in exact agreement about chronology - the obvious example being financial transactions. A lot of markets were closed for the leap second and many banks still suspend all transactions during any change of local time to mitigate the risk of error. Even in applications where we don't particularly care, th…

And when processing satellite data.. if you're not in agreement of the time, that one second error results in a ~7km geographical error for your typical polar orbit weather satellite.

Re: Australia/Lord_Howe is the weirdest timezone

#204
Another fun fact about timezones: if the government abolishes DST one year, and then moves some timezones an hour the next year, it creates a wild mess. Especially when you're building an Android app. Especially when it's the early 2010s so the timezone database is built into the system image but most devices that run your app don't receive system updates at all.

Instead of picking the timezone with the correct offset and no DST, many people would adjust the time itself so the wrong timezone and the wrong unixtime cancel each other out so the clock "looks right". Not fun when you're doing math with timestamps, some of which are local and some come from the server.

Re: Australia/Lord_Howe is the weirdest timezone

#205

Nah, the weirdest time zone is Africa/Addis_Ababa, which nobody in Ethiopia follows. Instead the locals offset the time by 6 hours. So the AM cycle starts at dawn (i.e. 6am), and the PM cycle starts at dusk (i.e. 6pm). https://en.wikipedia.org/wiki/Time_in_Ethiopia

This is common across East Africa, including Kenya where I’m from. The night ends at 6:00AM, with 7:00AM being saa moja (first hour) of the day. Similarly, the day ends at 6:00PM (thenashara). Intuitively, this clock makes much more sense than the English clock. There’s rarely confusion between times because it’s embedded in the language.

Since it's pretty much on the Equator it makes a lot of sense to keep time like that -- days and nights have the same duration all year long. Such a system doesn't make sense for places that have wide variations between seasons, unless you also alter the length of the hours to match (which I think was done at some point somewhere in Europe, but I can't find any references)

Re: Australia/Lord_Howe is the weirdest timezone

#206

Earlier quoted context omitted.

> even if lunar time is well known The date of Ramadan is not well known because it's based on being able to see the moon from the local position on Earth. If the sky is particularly overcast for instance, then you cannot see the moon, regardless of where the moon is. This presents problems for implementation of the calendar into the workings of a nation state. Many countries that adopt the Islamic calendar officiall…

> The date of Ramadan is not well known because it's based on being able to see the moon from the local position on Earth. Note to self, look up what Islamic scholars think should be done about Ramadan on a moon base.

Not quite a moon base, but for Muslims on the ISS:

> the Malaysian government called a gathering of 150 Islamic legal scholars, scientists, and astronauts to create guidelines for Dr. Shukor. The scholars produced a fatwa, or non-binding Islamic legal opinion, intended to help future Muslim astronauts, which they translated into both Arabic and English. They wrote that in order to pray, Muslims in space should face Mecca if possible; but if not, they could face the Earth generally, or just face “wherever.” To decide when to pray and fast during Ramadan, the scholars wrote, Muslims should follow the time zone of the place they left on Earth, which in Dr. Shukor’s case was Kazakhstan. To prostrate during prayer in zero gravity, the scholars stated that the astronaut could make appropriate motions with their head, or simply imagine the common earthly motions.

I’m not an Islamic scholar (or a Muslim at all), so this is just speculation, but my guess is that if it were a permanent settlement, with people being born and living their whole lives on the moon base (so “where they left earth from” is not meaningful), they’d probably just settle on one permanent Earth time zone to follow; presumably either that of Mecca, or that of whatever country on Earth (if any) owns the base.

Re: Australia/Lord_Howe is the weirdest timezone

#207

I kind of thing a half hour daylight savings difference instead of an hour is a pretty low bar for the weirdest timezone. Almost any of the others are weirder: Antarctica/Troll definitely sounds weirder. The Moroccan and Gazan timezones that can't be expressed by the system as it was written because at least that means that they have some different kind of a rule, even if lunar time is well known. Same with the ones…

Came here looking for Troll - as far as I know it's the only one to have winter daylight savings time. Also it gets extra points for the name.

Re: Australia/Lord_Howe is the weirdest timezone

#208
post #88

"Running cron jobs on an hourly basis doesn’t in practice have very weird interactions with DST" Of course every sane person runs their default system clock on UTC and lets users pick their own local time. That way cron always does the "right thing"(TM).

That's true if you need to clean up temporary files every night or make a backup. But what if your cronjob has an effect in the physical world, locally? E.g. open the parking gates every morning. The world is inherently messy :-)

> That's true if you need to clean up temporary files every night or make a backup.

Making a backup is usually reserved for the quietest hours of the morning, so that it does not compete as much for resources with the normal operation of the system; in my experience, the quietest hour is usually around 4:00 local time.

Re: Australia/Lord_Howe is the weirdest timezone

#209

I kind of thing a half hour daylight savings difference instead of an hour is a pretty low bar for the weirdest timezone. Almost any of the others are weirder: Antarctica/Troll definitely sounds weirder. The Moroccan and Gazan timezones that can't be expressed by the system as it was written because at least that means that they have some different kind of a rule, even if lunar time is well known. Same with the ones…

> But I do agree with leap seconds: it's absolute trivia, not a useful thing for a programmer to know. By and large, I agree with this. But I've always found it a bit funny when a large organisation [1] says "our servers have sub-millisecond timing accuracy, thanks to GPS synchronization and these PCIe rubidium atomic clock cards we've developed" while at the same time saying [2] "we smear leapseconds over the course…

And then you validate against Microsoft's default `ClockSkew` of 5 minutes.
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