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Europe pushing for lunar time zone

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Re: Europe pushing for lunar time zone

#371

Post by zymhan »

yencabulator wrote: post #362
adastra22 wrote: post #352

Earlier quoted context omitted.

It's not drift. Time passes more quickly on the moon, to such an extent that there are 56 microseconds more each day on the lunar surface than on Earth. This is a an effect of general relativity. For everyday human-scale stuff, sure this doesn't matter. For precise scientific and industrial use cases, it does.

I repeat myself: What's the difference between taking a good clock to the moon, where it runs 56 microseconds fast each day, versus having a less-tuned oscillator that runs 56 microseconds fast each day?

Because of the need to convert between the two systems.

It's not just about keeping time on the moon. It's reconciling that with other places in the solar system

Re: Europe pushing for lunar time zone

#372

Post by nixpulvis »

fluoridation wrote: post #338
makeitdouble wrote: post #329

Earlier quoted context omitted.

I read it as computers being the primary target for any clock system

Computers don't really care about the current wall time. They just care about measuring time between events. If a piece of software about the current day of the week it's only because a person cares about it and wants to do something special on certain days of the week. So, yes, time systems should be designed around the needs of people.

I believe time systems should be designed around the physics of the natural systems we inhabit. This may help us mere humans better harmonize with the rest of that which makes up our worlds.

This may sound a bit hippy dippy at first, but just consider how much light pollution effect other creatures, for a quick example.

Re: Europe pushing for lunar time zone

#373

Post by [deleted] »

wmanley wrote: post #290
jjk166 wrote: post #275

Earlier quoted context omitted.

> It would be near-impossible to make an analog clock, for example, Why would that be an issue? You still have the hours hand make a full rotation in one period, and you make markings at each hour. You just have separate markings at 24 o'clock and 0 o'clock.

and the minute hand?

[deleted]

Re: Europe pushing for lunar time zone

#374

Post by yencabulator »

zymhan wrote: post #371
yencabulator wrote: post #362

Earlier quoted context omitted.

I repeat myself: What's the difference between taking a good clock to the moon, where it runs 56 microseconds fast each day, versus having a less-tuned oscillator that runs 56 microseconds fast each day?

Because of the need to convert between the two systems. It's not just about keeping time on the moon. It's reconciling that with other places in the solar system

If they run on UTC, and correct for drift like any clock needs to do, what else is there? What conversion, what two systems?

Re: Europe pushing for lunar time zone

#375

Post by trompetenaccoun »

coldpie wrote: post #361
trompetenaccoun wrote: post #336

Earlier quoted context omitted.

Currently you have to know all your timezones and do the conversions in your head if you travel a lot for example. Additionally the organizers of many events and conferences, even very international ones, do not use UTC. So no, UTC doesn't solve that problem in practical terms. If the entire world used UTC for their local time, then it would be a similar solution. I personally wouldn't mind that actually. It would ta…

You have to know how the sun behaves at your local position relative to the universal time regardless of whether we call that knowledge "time zones" or something else. It sounds like what you want is for everyone to be more explicit about their time zone: instead of saying "the conference starts at 3 PM" they should say, "the conference starts at 3 PM UTC-6", right? From that you can easily derive that it's 9 PM UTC,…

Maybe you haven't experienced it yet but it's not as simple. I live in different countries and regularly have to deal with this. There's often confusion about time zones. Sure, it's "just a simple" conversion in theory but firstly the point is that ideally you should not have to do this at all and secondly no one calls it "UTC-6". You're lucky if they add a time zone at all, and when they do it's usually "EST", "Beijing time", "Eastern" (which can be Australian, American or whatever, your job to know from context), etc. Then you have to deal with DST, but only in some countries during some parts of the year. And don't forget the countries that add half hours, or Nepal which is extra special with an additional 3/4 because why not. It's utter madness.

Unless you're a savant who can remember all regions with corresponding time zones and all the exceptions, you'd be looking this up, which is what people normally do.

Re: Europe pushing for lunar time zone

#376

Post by jjk166 »

wmanley wrote: post #290
jjk166 wrote: post #275

Earlier quoted context omitted.

> It would be near-impossible to make an analog clock, for example, Why would that be an issue? You still have the hours hand make a full rotation in one period, and you make markings at each hour. You just have separate markings at 24 o'clock and 0 o'clock.

and the minute hand?

Still goes at 1 rotation per hour. You put the minute markings on another wheel to precess each day. The hour and minute hands won't form the same angle at the same time each day, but it will still tell the correct time.

Re: Europe pushing for lunar time zone

#377

Post by dsfyu404ed »

tdba wrote: post #355
dsfyu404ed wrote: post #345

Earlier quoted context omitted.

Everyone says this but reality never seems to work out that way when push comes to shove. Will you be singing that tune when a religious minority you hate moves there, establishes a theocratic government, starts teaching women to read, hanging undesirables and troublemakers and regressing on pretty much every human right your ancestors died for, bonus points for starting a war with the locals. That said, in the histo…

You are of course talking about the Ottoman conquest of Constantinople.

I was thinking the English settlement of eastern Massachusetts and the Connecticut river valley but I guess that works too.

Re: Europe pushing for lunar time zone

#378

Post by skissane »

RedNifre wrote: post #287
skissane wrote: post #178

Earlier quoted context omitted.

For software that runs on Mars, I think "Mars date/time" has to be a brand new set of APIs and data types. The existing date/time APIs/types are for Earth times only. The "local time zone" on Mars would just be UTC. That way there wouldn't be much possibility of bugs based on confusing Earth and Mars time scales – all pre-existing software would still work with Earth date/times, and anything that needed to deal with…

No, Mars has less mass than Earth, so if you use Earth UTC, Mars seconds will be longer than SI seconds, which does not seem like a good idea.

I think you misunderstood my point - I was saying make both Earth UTC and some Martian time scale available, just use a new API and data types for the latter. Which one to use in any given use case will be up to the application developer.

Re: Europe pushing for lunar time zone

#379

Post by adastra22 »

yencabulator wrote: post #374
zymhan wrote: post #371

Earlier quoted context omitted.

Because of the need to convert between the two systems. It's not just about keeping time on the moon. It's reconciling that with other places in the solar system

If they run on UTC, and correct for drift like any clock needs to do, what else is there? What conversion, what two systems?

Clock slew is unacceptable for many use cases. For keeping system time on a UNIX server or for astronaut watches, sure. For many other things you need a precise and accurate count of how many micro/nano/pico seconds have passed. You can’t just have one second suddenly be N nanoseconds longer and expect sensitive experiments to not be affected.

Re: Europe pushing for lunar time zone

#380

Post by ted_dunning »

eru wrote: post #168
WastingMyTime89 wrote: post #132

Earlier quoted context omitted.

It didn’t work in 1793 when it was mandated by the Convention despite the rest of the metric system taking roots. It was unlikely that a rebrand by a greedy Swiss corporation would make it more popular. Plus, current time keeping already use superior base systems. 12 and 60 are both highly composite numbers. Using a decimal system would be a step back. I wish we had symbols for 10 and 11 however.

In decimal, in general in decimal to write a fractions you need an infinite number of digits (with repetition). We have convenient notation for that repetition. A few special fractions can be written with finitely many digits. Using base 12 or 60 you are in the same situation. If you want elegance, you should cut down on the number of special cases. Hence I would suggest to use a base like 11 or 59. That way more fra…

You are off here a bit.

ALL decimal, base 12 and base 60 expansions of rational numbers end in a repeating sequence. Just like base 11 and 59.

The only difference between 1/7 and 1/5 in decimal is that for the 1/7, the repeating sequence is 7 digits long (142857) and for 1/5 the repeating sequence is 1 digit long (0). In base 12, 1/5 has a 4 digit repeating sequence (2497).

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