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Europe pushing for lunar time zone

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Re: Europe pushing for lunar time zone

#311

Post by nixpulvis »

yencabulator wrote: post #306

I really fail to see why they wouldn't just use UTC. > There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. And all computer clocks need to be corrected for drift anyway. Standard mechanisms for dealing with unruly oscill…

True, but UTC drift calculations on earth are different from on the moon. Fundamentally there is another time standard on the moon. How we account for that is up to us, but it makes sense to formalize this IMO. You could perhaps try to first derive a galactic or stelar time standard, then make both the moon's and earth's a derivative, but that seems even more complex in a way, though perhaps the most elegant in another.

Point is, the moon experiences time slightly differently than the earth, so having a clear reference will help synchronization, both to familiar geocentric standards as well as while on the moon.

I don't think we should define days around the petty need of humans. Even calendars are setup to map roughly to larger systems like phases of the moon / tides or orbits around the sun. The fact that an astronaught needs to sleep many times in a single "day" should not be a concern for the reference day/time, but could perhaps influence the time zones?

Re: Europe pushing for lunar time zone

#312

Post by ElectricalUnion »

Kwpolska wrote: post #215
mschuster91 wrote: post #156

Earlier quoted context omitted.

The worst problem with timezones IMO is that they are way too big [1], compared to what they should be if the world were equally divided into 24 hour "strips". Europe for example has CET which stretches all the way west to Spain, despite UTC+1 ending somewhere along the French-German border - so Spain and France are 1 hour "ahead" despite not needing to. [1] https://www.timeanddate.com/time/map/

This might be a “problem” for people who like arbitrary lines to define their lives. Keeping most of Europe on one time zone lets people from different neighbouring and culturally close countries work together without needing to think about time zones.

If keeping most of Europe on one timezone lets people work together without needing to think about time zones, so does unifying the entire earth on a single TAI or UTC "timezone".

Re: Europe pushing for lunar time zone

#313

Post by osigurdson »

yencabulator wrote: post #306

I really fail to see why they wouldn't just use UTC. > There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. And all computer clocks need to be corrected for drift anyway. Standard mechanisms for dealing with unruly oscill…

Fully agree. I think some of the proposed lunar base locations have near constant sunlight for much of the year - rendering any mapping to period dark/light periods mostly irrelevant.

The impact of gravity is relevant of course. There is no reason not to use Earth as the reference however.

Re: Europe pushing for lunar time zone

#314

Post by shepherdjerred »

skissane wrote: post #183
cornholio wrote: post #125

I am a proponent of a Martian timekeeping system where each day has 24 hours 39 minutes and 35.244 seconds and all the rest of time units have standard lengths. For example, at midnight your martian clock would show the time as 24:39:35 for a fraction of a second, then wound back to 00:00:00. The calendar then would track the Earth calendar as close as possible, with shortened months to accommodate for the longer day…

> The calendar then would track the Earth calendar as close as possible, with shortened months to accommodate for the longer days. Why bother with months? Why not just count weeks? You could use something like the ISO 8601 week calendar – the year is divided into weeks. Weeks run Monday (1) to Sunday (7). Every year beings on a Monday – ISO 8601 has two years, the Gregorian year (starts on 1 January) and the ISO week…

Months are nice to have

Re: Europe pushing for lunar time zone

#316

Post by starkd »

nixpulvis wrote: post #311
yencabulator wrote: post #306

I really fail to see why they wouldn't just use UTC. > There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. And all computer clocks need to be corrected for drift anyway. Standard mechanisms for dealing with unruly oscill…

True, but UTC drift calculations on earth are different from on the moon. Fundamentally there is another time standard on the moon. How we account for that is up to us, but it makes sense to formalize this IMO. You could perhaps try to first derive a galactic or stelar time standard, then make both the moon's and earth's a derivative, but that seems even more complex in a way, though perhaps the most elegant in anoth…

>> I don't think we should define days around the petty need of humans.

Why not? Are you being considerate for alien life? As far as we know, humans are the only ones who are going to use it.

Re: Europe pushing for lunar time zone

#317

Post by cornholio »

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?

Separate inner markings, like on most 24 hour earth clocks I find on Google images. When you've lost clean divisibility with 5, conflating the dials to make every hour house 2.5 minutes is already not a nice design.

Of course, you need mechanically handle the jumping ahead of the minutes and seconds arms.

What you get tends to look like a very precise chronometer, the type a Mars scientist would wear.

Re: Europe pushing for lunar time zone

#318

Post by yencabulator »

nixpulvis wrote: post #311
yencabulator wrote: post #306

I really fail to see why they wouldn't just use UTC. > There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. And all computer clocks need to be corrected for drift anyway. Standard mechanisms for dealing with unruly oscill…

True, but UTC drift calculations on earth are different from on the moon. Fundamentally there is another time standard on the moon. How we account for that is up to us, but it makes sense to formalize this IMO. You could perhaps try to first derive a galactic or stelar time standard, then make both the moon's and earth's a derivative, but that seems even more complex in a way, though perhaps the most elegant in anoth…

> True, but UTC drift calculations on earth are different from on the moon.

Hey reference clock, what time do you see? Oh, it's X? And I'm at Y? Okay, I'll adjust my drift correction factor to Z.

They might drift more than good modern-day clocks, and the latency to the reference clock might be higher, but the basic mechanism of correcting for the drift shouldn't be any different.

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?

Re: Europe pushing for lunar time zone

#319

Post by kelseyfrog »

cornholio wrote: post #125

I am a proponent of a Martian timekeeping system where each day has 24 hours 39 minutes and 35.244 seconds and all the rest of time units have standard lengths. For example, at midnight your martian clock would show the time as 24:39:35 for a fraction of a second, then wound back to 00:00:00. The calendar then would track the Earth calendar as close as possible, with shortened months to accommodate for the longer day…

Despite this, I'm an advocate for martian self-determination when it comes to deciding their timekeeping system. Earthlings, despite their good intentions, should stay out of the matter categorically.

Re: Europe pushing for lunar time zone

#320

Post by msm_ »

eru wrote: post #159
cornholio wrote: post #141

Earlier quoted context omitted.

It's basically the same thing, but harder to achieve technically because many things assume clocks are moving all the time. For example timers and timeouts are frequently implemented as loops polling system time has reached a certain future value. Many things break or malfunction if a large number of things happen at the same time, for example logging, crons etc. Imagine investigating a cybersecurity event perpetrate…

Those things should be on UTC anyway (even on earth). Timezones are just for displaying to humans.

How is stopping the clock for 40 minutes human friendly? I'm a night owl and there are many things in my life that happen between 00:00 and 00:40, can't imagine pretending they all somehow happen in the same moment.
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