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Europe pushing for lunar time zone

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Re: Europe pushing for lunar time zone

#161

Post by euroderf »

cyberpunk wrote: post #135
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…

I prefer KSR's "time gap". At midnight on mars, everyone just gets a 40 minute period where the clocks don't move.

Cue sci-fi dystopia where the totalitarian Mars gov't gases (or somehow otherwise knocks out) everyone for 40 minutes while they search the place and haul off dissidents.

Re: Europe pushing for lunar time zone

#162

Post by Xylakant »

ajuc wrote: post #154
Al-Khwarizmi wrote: post #143

"Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said". I have no technical knowledge about clocks at all, but this sentence sounds odd to me, shouldn't there be a lot of different clock technologies that work in different ways? Or are they saying this because there is only one "best" technology for NASA purposes and that one is off by 56 us on the moon?

They should have written "time runs faster on the Moon than on Earth". Clocks just measure it. You can't solve this with a better clock :)

But you could fix it with a sufficiently heavy clock.

Re: Europe pushing for lunar time zone

#163

Post by wongarsu »

claviola wrote: post #139
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…

Do you honestly consider modifying the core idea of the 24 hour day to be a "slight tweak"? I can't even imagine how many different things rely on that assumption. (and I'm sorry, but what does "naming months and seasons in Mars" have to do with this?)

You have basically three options for timekeeping on mars: adjust the day, adjust the second, or give up on days syncing with the (apparent) movement of the sun.

The first option breaks mostly assumptions made in software and processes, the second mostly assumptions made in hardware, and the third breaks human's circadian rythm (a 23 or 25 hour rythm isn't a big deal, but it has to sync to light).

Of those three, the things that rely on 24 hour days seem to be the easiest to change. Though there is precedent both to messing with the length of a day (a leap second makes the day one second longer, making 23:59:60 a valid time) and the length of a second (google pretends like seconds are slightly longer as an alternative way to deal with leap seconds)

Re: Europe pushing for lunar time zone

#165

Post by quickthrower2 »

I couldn’t read it all before a paywall/ad thing popped up but I am interested in why.

One reason you want the days to reflect the moons rotations around the earth somehow.

Another is you want it to be the time at the moons centre of gravity for relativistic reasons.

Re: Europe pushing for lunar time zone

#166

Post by medstrom »

phicoh wrote: post #148
Al-Khwarizmi wrote: post #143

"Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said". I have no technical knowledge about clocks at all, but this sentence sounds odd to me, shouldn't there be a lot of different clock technologies that work in different ways? Or are they saying this because there is only one "best" technology for NASA purposes and that one is off by 56 us on the moon?

No it is pesky Einstein guy with his general relativity. The bigger problem is that our timekeeping is earth based. The time definition should have been based on deep space, with corrections for time on earth. So earth clock are slow with respect to clocks in deep space. Clocks on the moon are less slow are therefore faster than on earth

Not a physicist, but I was led to understand there is no universal frame of reference. You can't base time on deep space as if time was the same across all deep space, because it isn't. Right? A local time "correction" is easy when you compare against exactly one other point in space but if you want something like an universe-wide UTC that everyone can correct against, it can't be done. Although I don't really understand why.

Re: Europe pushing for lunar time zone

#168

Post by eru »

WastingMyTime89 wrote: post #132
sen wrote: post #106

Earlier quoted context omitted.

I was so convinced .beats would take over the world (or solar system in this case). I had their watch, I installed their task-bar clock plugin for Windows 98, I harped on about it to my friends... a surprising number of which actually agreed it was a good idea. Then it just kinda fizzled out. I'm still upset it didn't take off.

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 fractions will be covered by the general case.

Base 11 also works well for counting on your fingers. (Though base 6 works for that one as well.)

Re: Europe pushing for lunar time zone

#170

Post by WastingMyTime89 »

cyborgx7 wrote: post #140
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.

Having your unit system in the same base as your number system infinitely outweighs any advantages derived from the having a higher number of factors or whatever. If you want to switch out number system, and then change the unit system alongside that, I'll hear you out. But skipping the number system and doing it at the unit level is always dead on arrival as an argument.

If it were the case, people would have switched massively to a decimal time keeping system.

The fact they did not is proof enough for me that using the same base than our number system isn't relevant. It makes sense intuitively because it's extremely rare that we have to go above 24 for hours and sixty for minutes while we divide these time periods fairly often.

I would gladly switch to base 12 just to have simpler multiplication tables (0, 1, 2, 3, 4, 6, 8 and 10 are really simple, 9 and A are fine while 5, 7 and B are annoying) but I am no fool and realise it's never going to happen.

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