Definitions Deconstructed
Leap Year
S. G. Lacey
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Definition:
A year that contains 366 days, with February 29th as the additional diurnal; occurring in years whose last 2 digits are evenly divisible by 4, except for centenary years not divisible by 400. [REF]
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Deconstruction:
Sorry if you were told there would be no math today.
Based on this technical definition, there’s a little more arithmetic associated with a leap year than we were led to believe as children.
From a cosmological standpoint, the Earth rotates around the sun roughly every 365.242189 days, or 365 days, 5 hours, 48 minutes, and 45 seconds. This level of precision, with 6 random decimal places, explains why it’s so difficult to come up with a simple leap year format.
This complexity hasn’t stopped innovative thinkers from trying to establish functional annual protocols over the past several millennia. Reviewing a brief history of calendars helps provide some context on handling this astronomy anomaly.
Timekeeping for early civilizations was based on lunisolar datebooks, which reference both the moon and the sun, the 2 most visible objects in the sky, during night and day respectively. There is roughly a 11-day gap between monthly lunar rhythm, and Earth’s annual orbit around sun. Ancient Hebrew, Chinese, and Buddhist calendars all used this hybrid format, hence the 12-year, animal-based, cadence still adhered to in many Asian countries.
As with many elements of modern life, major changes were made around the historical transition from BC to AD. The early Roman calendar had 10 regular months, then a winter period of undefined length, to account for the discrepancy between the moon and sun rotations. They utilized a 23-day intercalary month, known as Mercedonius, at the end of February, to tie their calendar back to the solar cadence.
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As a result, many Roman citizens were not even able to keep track of what year it was. Clearly, there had to be a better way than this amorphous, arbitrary approach.
Julius Caesar is known for a multitude of significant achievements. The supreme leader of the Roman Empire, at the height of their power. Military prowess, personified by the conquest of Gaul. Clever monetary policies, to sure up the financial sector, and mitigate poverty. Despite a busy schedule, he even found time to revamp the entire timekeeping landscape.
Caesar is credited with laying the groundwork for the modern calendar, most notably with the establishment of a “Leap Day” in February. Inspiration was taken from the Egyptian’s, whose livelihood was shaped explicitly by solar cycles, under the infamous god Ra. When you live in a desert, the sun is a perpetual influence on life.
In this era of Rome, many annual occurrences of import to the people had drifted an unacceptably far distance from their historically seasonal timeframe. 2 extra months added to the Roman calendar in 46 BC got everything on track. The official Julian Calendar was initiated on January 1st, 45 BC. This system, with 12 formalized months, added one extra day at the end of February every 4 years.
This sounds very similar to the modern format, but a final tweak was needed. Not surprisingly, this modification was executed by a clergyman, with both religious and administrative acuity. Pope Gregory XIII.
By the 16th century, despite all of Caesar’s foresight, Easter, one of the most sacred dates on the Christian agenda, had shifted by 10 days. This celebration was traditionally observed on the first full moon after the vernal equinox, thereby combining both lunar and solar astrological activities.
Pope Gregory XIII, guided by a pair of esteemed astronomers, decided to rectify this issue once and for all. With a greater understanding of the solar system, afforded by the scientific revelations of the Renaissance period, the Earth’s orbital timing was known with much more precision.
The Gregorian Calendar corrected the slight calculation error of Caesar’s 365.25 annual day assumption with one simple change. Moving forward, the leap day would be eliminated from centurial years not divisible by 400.
At this point, with a 356.2425 cadence, the accuracy has moved into the 4th decimal point. While this 16th century system isn’t prefect, its close enough for most commoners, without causing any major disruptions to everyday logistics. However, over the long arc of time, even menial differences are magnified.
What day would it be at the time of this post, if the calendar was not revamped by Julius Caesar, then adjusted by Pope Gregory XIII?
Per Caesar’s original 45 BC mandate of a quadrennial leap day, currently we would already be in mid-March, with the NCAA basketball tournament ramping up, spring on its way, and Easter, a key factor in the original adjustment, right around the corner.
The Gregorian tweak, circa 1582, is much more precise, but still not exact. Since implementation, this approach has drifted from its overarching solar guidance by a whopping 3 minutes. That’s less time than it takes to read this article, over the course of 400+ years, and humanity won’t lose a full day until nearly the start of the 5th millennium.
Clearly, Renaissance era astronomers were pretty proficient.
This topic demonstrates that the passage of time is subjective, fleeting, and transitory. Potentially humanity’s closest tangible connection to time travel exists in the form of the current leap day and year mechanics.
Never fear. The modern scientific community has come up with a way to solve this chronological conundrum. The leap second.
Atomic clocks, the earth-based, gold standard, for timekeeping, perpetually deviate from the Earth’s solar orbit, most notably due to the gradual slowing of our planet’s rotation, combined with other atmospheric irregularities.
Leap seconds occur periodically in Coordinated Universal Time (UTC). Despite the overarching goal of scientific exactness, these intermittent micro-adjustments are surprisingly not dictated by a regimented set of rules. Apparently, the cosmos is too dynamic to predict, even with our vastly refined analysis capabilities.
Leap seconds, the last of which occurred at the end of 2016, are announced 6 months in advance. These step-change shifts to all clocks worldwide are becoming increasingly challenging to execute in our computerized, digital world. Thus, the concept of the leap second may be truly fleeting.
Activities which happened on a leap day theoretically only occur every 4 years. This makes for some interesting timing for birthdays, anniversaries, and other annual celebrations.
Those born on February 29th are dubbed leaplings, leapers, or leapsters. Only 1 out of every 1461 people is born on a leap day, resulting on nearly 190k citizens in the U.S., and only 5 million such individuals worldwide.
The list of famous leaplings includes many individuals of note: Pope Paul III (1468 = Bishop), Ann Lee (1736 = Quakers Founder), Gioacchino Rossini (1792 = Italian Composer), Augusta Savage (1892 = African American Sculptor), Dinah Shore (1916 = Singer), Dennis Farina (1944 = Actor), Tony Robbins (1960 = Financial Coach), Ja Rule (1976 = Rapper), Cam Ward (1984 = Hockey Player).
Typically, these individuals celebrate their birthdays on February 28th, March 1st, or both. No reason not to take advantage of the cards you’re dealt. Legal birthday date acknowledgement varies based on each home country’s policies.
Two anomalies highlight the true rarities associated with leap year lifecycle dynamics. James Milne Wilson, the 8th premier of Tasmania, is documented to being born and dying on leap days, in 1812 and 1880 respectively. Even more impressive, the Keoghs, of Irish origin, produced 3 consecutive generations birthed on February 29th, in 1940, 1964, and 1996. That’s some effective family planning.
Marriage is another event often marked by repeated anniversary celebration. As a result, leap day offers a unique opportunity to create new nuptial policies around this calendar anomaly.
Starting in 5th century Ireland, per the decree of the honorable St. Patrick, on leap day, women were allowed to propose to men. To this day, throughout the British Isles, if the man rejects a woman’s foray, he needs to buy her a pair of fancy gloves to cover up the lack of a ring. Similarly, both Greek and Italian traditions suggests that it’s bad luck to get married on leap day.
Clearly, the Europeans love their superstitions.
These crazy theories even extend beyond humans to other animals. A well-known Scottish proverb claims "Leap year was ne'er a good sheep year."; a sentiment which many highland farmers still strictly adhere to.
Several notable historical events have occurred on this intermittent day of the modern calendar.
Way back in 1692, just over a century after the Gregorian Calendar was adopted, its religious overtones came home to roost. On February 29th of this year, 3 residents of Salem, MA were accused of conjuring, sparking the New World witch hunt trials which live in infamy.
Exactly 404 years later, on a completely different continent, the Bosnian capital of Sarajevo was officially freed from its Serbian oppressors. This 4-year conflict, with blockades initiated just a month after the 1992 leap day, represents the longest sustained siege in the history of modern warfare.
While numerous other worldwide activities have occurred on February 29th, it’s surprising how few events of note have taken place on this intermittent day. Maybe everyone is too busy contemplating the reason for such a calendar oddity.
Surprisingly, despite the aligned quadrennial, even number, cadence, Winter Olympics activities have never occurred on a leap day. The Closing Ceremony for the 1960 Squaw Valley, U.S.A. and 1988 Calgary, Canada gatherings both occurred on February 28th, potentially to avoid confusion with documenting daily activities which don’t occur every year.
With the switching of the Winter Games to a 2-year offset cadence starting with Lillehammer, Norway in 1994, this frozen sporting celebration is no longer on a leap year cadence. Even in the southern hemisphere, it’s unlikely the Summer Olympics will ever occur during February.
Despite the predicable cadence of the modern calendar, albeit with a few irregularities, calculation errors still occur in this modern, digital world.
Everyone remembers the theorized Y2K computer bug. And the fact that it was a complete dud from an electronic execution standpoint. Interestingly, an equally relevant computing challenge occurred less than 2 months later.
The year 2000 was devisable by 4, for even the most menial mathematician. However, this was the 1st centennial rollover since 1600 which qualified as a true leap year, at which time computing power was clearly substantial less advanced. Considering the convoluted calendar rules, it’s understandable that a few, less proficient, programmers missed this nuance.
Fortunately, well-funded governmental programs worldwide focused not just on the known Y2K integrated circuit snag, but also the more hidden and confusing centennial leap year math. As a result, there were no major hiccups with date processing during either instance, and now, a few decades later, mainframes have advanced infinitely further from a timekeeping standpoint.
While 2000, and subsequent leap days, have come and gone without incident, in the digital and physical realms, the most challenging era for computing occurred in the 1990’s, when programming was still in its infancy.
February 29th, 1996 alone was personified by all manner of information technology snafus.
The inability of over 60,000 willing customers to purchase month-end lottery tickets in Arizona, with a massive jackpot at stake. A New Zealand aluminum smelting operation literally melting down, as the 366 day wasn’t part of their manufacturing protocols. NYC cab fares, scheduled to be raised on March 1st, incrementing up a day early, much to the chagrin of many drunken riders. Diagnostic lab equipment at a Great Britain hospital completely shut down, forcing rapid medical outsourcing to keep patients alive.
Fortunately, technology has advanced significantly since then, with cybersecurity systems and secure payment processing taking precedent over mundane numerical timekeeping tasks. The next quadrennial non-leap year will occur in 2100, which gives programmers, and society as a whole, plenty of time to make the necessary electronic adjustments.
If you get some free time early in 2024, head to Anthony, Texas, the self-proclaimed leap year capital of the world, boasting a raucous festival during each quadrennial occurrence. Plan your procreation activities accordingly, if you’re scheming to move your offspring into ratified air, and minimize lifetime the distribution of presents.
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