51–60 of 119 posts
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These are particularly interesting because they isolate the one part of time that is completely made up: the week. Days, months, years have natural markers - but weeks and particularly days of the week are a totally arbitrary coordination function.
Aren't modern months made up as well? They are not in sync with lunar cycles anymore.
1 year = 360 days + 5 days of Festivus (6 for leap year)
360 days = 12 months
1 month = 3 weeks
1 week = 10 days
10 days = 6 work days + 4 day weekend
Incorporate the metric clock into a "metric" calendar: 1 year = 360 days + 5 days of Festivus (6 for leap year) 360 days = 12 months 1 month = 3 weeks 1 week = 10 days 10 days = 6 work days + 4 day weekend
On the Moon or even Mars it's a bit irrelevant because you're not following the Sun anyway. But let's talk sci-fi: what if there is a habitable colony where the day is 26h30m. What do you actually do?
Planets can use a local solar time and calendar. Habitats in free space could just move to Unix time and use a 100 kilosecond day.
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These are particularly interesting because they isolate the one part of time that is completely made up: the week. Days, months, years have natural markers - but weeks and particularly days of the week are a totally arbitrary coordination function.
Well, seconds, minutes, and hours are also arbitrary.
24ths and 60ths are useful fractions because 24 and 60 are highly composite numbers, i.e. they have many divisors. 60 is a particularly good choice, since it's a "superior highly composite" number; and so is 12, if we consider an AM or PM period, rather than a full rotation.
Such divisibility was important before the invention/discovery of general fractions (i.e. the rational numbers). Babylonian arithmetic used something akin to base 60 floating-point, which could represent halves, thirds, quarters, fifths, and their sums and products (but not e.g. sevenths, or reciprocals of higher primes; in the same way base 10 floating-point can't represent a third).
Minute, meaning "small", describes the shifting of the radix point in such a base 60 floating-point system. Second, as in the ordinal 2nd, describes a further shift of radix point; and likewise for thirds, fourths, etc. for ever-smaller increments.
I think the day needs time units which are factors of 10x or 1000x to match SI prefixes. I give translations assuming current solar day length and current normal units: - deciday (2.4 hrs) - centiday (~0.24 hrs, ~14.4 minutes) - milliday (~1.44 minutes, ~86.4 seconds) - microday (~86.4 milliseconds) But, to really get into the decimal clock, we want to also extend this into culturally useful multi-day units. - decada…
The revolutionary French tried decimal timekeeping, but no amount of guillotines could make it stick. Planetarily, we only need to slow the Earth's rotation by 1.46%, so that the year becomes 360 days (1 day = 1° of revolution) and I can sleep an extra 21 minutes.
https://xkcd.com/320/ https://www.explainxkcd.com/wiki/index.php/320:_28-Hour_Day
24-hour analogue clocks should have midnight at the bottom and noon at the top. Why? Because that's the way the sun moves. See https://sunclock.net
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That's pretty neat. The ? (help) link and the speed up button overlap on my browser (firefox on android, url bar on the bottom). My email is in my profile, I can send a screenshot if you need it.
Thanks toast0 - that's my bad, there was an old dev button that was shifting everything over causing the issue because I always mix up "visibility hidden" with "display none" in CSS. Should be fixed now!