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Terran Computational Calendar Introduces Minimonths, Year Bases, and Datemods
First time accepted submitter TC+0 (3672227) writes "Inspired by comments regarding its first incarnation, the Terran Computational Calendar's recent redefinition now includes dynamic support for 'leap duration', 'year bases', and 'datemods'. Here's the new abstract from terrancalendar.com (wikia mirror) captured at 44.5.20,6.26.48 TC+7H:
Synchronized with the northern winter solstice, the terran computational calendar began roughly* 10 days before the UNIX Epoch. Each year is composed of 13 identical 28-day months, followed by a 'minimonth' that houses leap days (one most years and two every 4th but not 128th year) and leap seconds (issued by the IERS during that year). Each date is an unambiguous instant in time that exploits zero-based numbering and a handful of delimiters to represent the number of years and constant length months, days, hours, minutes, and seconds that have elapsed since 0TC (the calendar's starting point). An optional 'year base' may be applied to ignore erratic leap duration. Arithmetic date adjusting 'datemods' can be applied to define things like weeks, quarters, and regional times."
Synchronized with the northern winter solstice, the terran computational calendar began roughly* 10 days before the UNIX Epoch. Each year is composed of 13 identical 28-day months, followed by a 'minimonth' that houses leap days (one most years and two every 4th but not 128th year) and leap seconds (issued by the IERS during that year). Each date is an unambiguous instant in time that exploits zero-based numbering and a handful of delimiters to represent the number of years and constant length months, days, hours, minutes, and seconds that have elapsed since 0TC (the calendar's starting point). An optional 'year base' may be applied to ignore erratic leap duration. Arithmetic date adjusting 'datemods' can be applied to define things like weeks, quarters, and regional times."
OK, sure, you're invented your own calendar. I'm sure it's awesome.
But nobody will use it.
But, hey, some people speak Klingon at parties in the hopes it will impress their friends.
Seriously, do you expect people to use this? Or is it purely an intellectual exercise?
I'm afraid I don't see the point.
Lost at C:>. Found at C.
... I'ld rather go back to Thermidor.
By default, the Terran Computational Calendar accounts for IERS issued leap seconds. But, Leap seconds can actually be ignored by applying a year base of 0. Therefore, the following two dates are the same instant in time: 44-05-20 22:16:41 TC (includes leap seconds), 44-05-20 22:17:06 TC0 (excludes all leap seconds)
And if you use Steven Wright's calendar, you can ignore sevens.
Synchronized with the northern winter solstice,
By their nature, solstices are notoriously difficult to determine empirically. Theoretically there is an instant when the the sun's declination reaches its minimum, but practically you'll have hours or even days of a change in declination that is too small to measure. Popular surviving calendars either rely on an equinox instead (Christian, Jewish), or pad several lunations after the solstice just to make sure (Chinese).
the terran computational calendar began roughly* 10 days before
Whose ephemeris?
Each year is composed of 13 identical 28-day months
Two figures that generally have nothing to do with natural phenomena. While it's true that a little more than one-third of all tropical years contain 13 synodic months, those months average to around 29.5 days each. There are cultures that care about the synodic month exclusively, and there are those that care about both the synodic month and the hebdomadal week, but I know of no major religion or regionally dominant culture that cares about only the hebdomadal week.
followed by a 'minimonth' that houses leap days (one most years and two every 4th but not 128th year)
We limit calendars to arithmetical processes because accuracy must be balanced with ease-of-use for human beings, and we tend to prefer powers of ten because that makes the arithmetic easier for humans. If you're going to insist on powers of two in your calendar, you're effectively requiring people to reach for some sort of computer to perform the algorithm for them (except for those rare few who enjoy performing long division). And if you're already doing that, there's no longer a reason to limit your calendar algorithm to arithmetical (or even algebraic) processes to begin with; just have a computer chew on the transcendental functions directly rather than limiting it to an arithmetical approximation to begin with. Shoehorning in a power of 2 is a compromise that satisfies nobody.
and leap seconds (issued by the IERS during that year). Each date is an unambiguous instant in time
Coordinated Universal Time and it's system of coordinated leap seconds is older than POSIX, and yet even today POSIX still can't get leap seconds right, insisting that each and every day is exactly 86 400 s long (which is a big part of why we're having our current Leap Second Holy War to begin with). IT has been kicking that can down the road for about 40 years. Why will an adoption of your calendar suddenly change that?
that exploits zero-based numbering
Programming languages can't agree where to start an array, but to my knowledge nobdoy is currently using a calendar with a "day 0" or "month 0" (let alone a "zeroth day" or "zeroth month"). Insisting on "zero-based numbering" doesn't solve anything, but rather dumps IT's own internal issues with counting onto the rest of the world.
Actually, back in the pagan days, there WERE 13 months
Embolismic months are not constant, but are inserted because there is a difference of about 11 days between 12 synodic months (~354 days) and one tropical year (~365 days). An embolismic month ends up being added approximately 7 years out of 19, by different algorithms according to different cultures. And even if you were intended to include Jews (and their occasional "Adar II") among your categorization of "pagans," even Christians keep track of embolismic lunations in reckoning the date of that faith's holiest day (in the Gregorian Calendar, May 30 is the first day of the seventh lunation out of thirteen in AD 2014). The only major religion that absolutely, positively insists on a year of 12 months for all purposes is Islam.
The year started in spring, and December was the 10th out of 13 months.
It was the tenth of ten months; the early Romans likely reckoned winter as extracalary. January and February (and Mercedonius/Intercalaris) were added later, probably when what passed for Roman astronomy became relatively more sophisticated. And it wasn't only "pagans" that insisted that March was the first month. The last major hold-out, the United Kingdom of Great Britain, didn't change until AD 1752 (AUC 2505). And not all "pagans" were or are Roman.
Seasons and duration of day are logical and meaningful things to base your units of time on. Nuclear decay and EM wavelengths are a rather illogical basis, as these things don't have a practical use or observation in the common life of humans in general. Days and seasons, on the other hand, have an apparent and obvious cycle, which can be observed without need of special equipment. Furthermore, they have an immediate and profound affect on our environment. This is the difference between light and dark, between heat and cold, between growth and recess. These cycles dictate when we can grow food, and how long we have to complete tasks. It therefore makes a great deal of sense that we would want to keep track of these things. The only failing, is that the larger units aren't always comprised of a whole number of the smaller units, as they are based on difference cycles, which are not actually related to eachother.
Now, on the other hand, if we lived on a starship or perhaps a space station unassociated with any particular planet, your timekeeping method could reasonably be arbitrary. You might choose to base it on the crew's mode average circadian rhythm, perhaps. In those circumstances, you would have eliminated the conditions that have inspired our current timekeeping system.
Learning about brewing beer, by brewing beer.