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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.
That is remarkably similar to what I used to use for a backup tape rotation once upon a time:
27 daily tapes labeled d1-d27
13 'monthly' tapes labeled m1-m13
1 year-end tape labeled appropriately
It was easy to manage since there was never any question which tape was 'next' or safe to reuse. Robotic tape libraries, software with better tape management, and eventually disk-to-disk backup make it obsolete, but I always did think that a 28x13+1(or2) calendar would be much more sensible than what we have now.
Not that I was ever silly enough to think that the world would adopt just because it makes more sense :)
... I'ld rather go back to Thermidor.
Sounds like the Ethiopian calendar.
12 months of 30 days plus a 13th month of 5 or 6 days (which are all holidays!).
Yea, my kids Ethiopian. Trying to keep track of the holidays is a nightmare. They're on a different day every year. Yet I have to honor his culture or something so I have to get out a slide rule to figure out when Christmas is every year.
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)
I prefer the Unix-based method from Vernor Vinge's A Deepness In the Sky. Everything is seconds based on the Unix epoch, with SI prefixes for longer periods -- ksecs (00:16:40), msecs (about 11.6 days), gsec (about 31.7 years), etc. With processing power as ubiquitous as it is, converting back and forth when planetary/celestial timing really matters is trivial. Most of our non-analog timing devices already work this way already, and those that don't (LED alarm clocks) are being phased out by devices that do work that way (smartphones). Granted this isn't any more likely to be used than the TCC, but at least it's cleaner.
"The Greens lynched a hacker in Chicago. Last month, but I think the body's still hanging from the old Water Tower."
Jesus (I believe the man existed, but not that he was a deity), do we have to complicate the Earth date system more???
Systems already break because it's complicated enough, and I have to set the times on microwave ovens and regular ovens often enough. We understand 12 months of varying lengths with a base 24 day cycle, isn't that enough. 221788790 seconds from the winter solstice???
A minimonth??? Seriously.
Time and dates are already defined for the inhabitants of the planet. And it works. Don't mess with it.
Next thing you know there will be pressure on the US to accept a non-English measurement system...
BlameBillCosby.com
You advocate a
( ) overly simplistic
approach to calendar reform. Your idea will not work. Here is why:
( ) having months of different lengths is irritating
( ) having one or two days per year which are part of no month is stupid
Specifically, your plan fails to account for:
( ) humans
( ) rational hatred for arbitrary change
( ) unpopularity of weird new month and day names
and the following philosophical objections may also apply:
( ) nobody is about to renumber every event in history
( ) good luck trying to move the Fourth of July
(x) the history of calendar reform is horrifically complicated and no amount of further calendar reform can make it simpler
Furthermore, this is what I think about you:
( ) sorry, but I don't think it would work
( ) this is a stupid idea, and you're a stupid person for suggesting it
How about we have a meeting? I'll send you a request in Outlook.
One problem with having all months evenly divisible by 7 day weeks is that your birthday will always land on the same day of the week. Born on Tuesday, your birthday will ALWAYS be on Tuesday. No hope of ever having a weekend birthday. Never ever. You think people will stand for that?!?
>"7 day weeks is that your birthday will always land on the same day of the week. Born on Tuesday, your birthday will ALWAYS be on Tuesday"
I devised my own calendar and the main feature is every day is 84 hours long, and all of them are Tuesdays!
My new calendar solution > yours!
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
This was considered, but ultimately, the terran computational calendar chose to define itself in terms of the 1977 definition of a TAI second:
"the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom" measured at the geoid (mean sea level)
Therefore, for the terran computational calendar, we actually know how much relativistic gravitational time dialation to account for, even if you are way out somewhere in a different star system, because it is the amount of relativistic gravitational time dialation that exists at mean sea level. So converting terran computational dates into future interstellar ones should be relatively (lol) easy. But, by it's name alone you've already realized that the Terran Computational Calendar is an earth based calendar and not generally expected to be used for interstellar travel.
Talking about a space travel, Barycentric Coordinate Time (TCB) and Geocentric Coordinate Time (TCG) are currently used. The former "performs exactly the same movements as the Solar system but is outside the system's gravity well" and the later "performs exactly the same movements as the Earth but is outside the Earth's gravity well".
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.
What more could you ask for?
I could ask for a calendar based on the moon, and years based on the solstices. At least that would make sense.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
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.
I don't care about Mini Months or Year Bases as much as the ability to have Year of the Depend Adult Undergarment, TrialSized Dove Bar or Perdue Wonderchicken. I want opportunistic branding to penetrate every orifice of my life.
It was the tenth of ten months; the early Romans likely reckoned winter as extracalary.
Yes, the very early Romans. Roman legend has the first king after Romulus added in January and February. While it may not have been that early, it likely predated the Republic. The 10-month calendar was probably obsolete long before 500 BCE.
January and February (and Mercedonius/Intercalaris) were added later, probably when what passed for Roman astronomy became relatively more sophisticated.
Yep -- though, contrary to popular belief, it probably wasn't Julius Caesar who moved the beginning of the year to January. The official year (which was named by the two consuls) was moved to January at least a century before Caesar's calendar reform. And January was basically treated as the first month of the civil year at least a few centuries before that (hence the name January, after Janus, who looked both ways toward the old and new years).
So, we're talking about a VERY old tradition here that was basically obsolete through almost all of historic Rome.
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).
It's a bit strange to equate the medieval dating technique putting New Year's on March 25th with the prehistoric Roman New Year's date of March 1st. Basically, after the old Roman tradition had been obsolete for a thousand years or more, some Christians decided that March 25th should be New Year's, since it was the day of the Annunciation, i.e., the conception of Jesus (9 months before Christmas). This kept in line with the idea of "The Year of Our Lord" (anno Domini), where we would date the years back to the time Christ was conceived -- a tradition which was first used at some point in medieval times.
So yeah, while some European countries through the medieval period and renaissance put New Year's at March 25, it wasn't really for anything related to the rationale for the original Roman practice. In fact, England didn't adopt this practice widely UNTIL the 12th century CE or so, which it then kept until the 1700s.
Oh, and by the way, even in countries (like England) where March 25th marked the beginning of some "year," there were often still other civil years that began on January 1st, depending on the legal or religious application involved. At the same time, and in the same country, there could be different "years" numbered beginning on January 1st, March 25th, December 25th, Easter, various points in September or November, and other times. (For some details on the situation in medieval England in this regard, see here.)
Yeah, I love ISO 8601 too: it's easy to use because it's standardized. But extremely strict standards arent always the best in every situation.
Besides the fact that the terran computational calendar's time of day is often in sync with UTC and that TC can account for UTC's IERS issued leap seconds, it has little else to do with UTC and a lot to do with the 1977 TAI redefinition (TAI = International Atomic Clock). UTC works well for dates after 1977, but exact dates before that are iffy especially before 1972 when leap seconds were treated differently. In addition to that, UTC makes it a little hard to work with leap seconds when it comes to UTC. I haven't created an complete implementation of UTC myself, and I wouldn't want to. The terran computational algorithm is relatively simple to implement, even with it's dynamics.
Standardizing the terran computational calendar would be much easier than standardizing UTC, but we all know that's it's adoption on any grand scale any time soon is unrealistic. But... I'm not convinced that grandscale adoption is really it's true purpose.