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Why is the leap day on February 29th?

Why is the leap day on February 29th?

Every four years, besides some certain years, we have a leap year, where a 29th day is added to February in the Gregorian calendar, making the year 366 days long, rather than 365. This is to make up for the fact that a true astronomical year is not exactly 365 days.

My question is, why is February 29th the leap day? Is there any specific event or special occasion that occurred on February 29th?


The ancient Romans used to have the new year at the end of February. To fit the lunar and solar calendars, an extra month was sometimes added after February. This practice continued even after the months were shifted so that new year moved to where it is now (this shift is the reason why we have e.g. "december" 'tenth month', as number twelve). This proved to be problematic, as it was the Pontifex maximus who decided when to add this extra month, which was sometimes forgotten, or done/not done to gain political advantage. With the Julian reform, the months got the length we are used to, and the leap days as we know them were added.

See wikipedia on February for a somewhat longer history.


The Wikipedia reference on February omits quite a bit of information. Simply put, the Roman religious year ended on 23 February (a.d. VII Kal. Mart. in the Roman counting backward and inclusively way… i.e., the 7th [6th in our counting] day before the first of March), with the Feast of Terminalia. (Before the Julian calendar, if they inserted an Intercalary month, February was in fact cut short at 23 days and the extra month then inserted between February and March.) Thus, when the Julian calendar was introduced, the natural place to insert a day was right after that. So in leap years, instead of the 24th day of February being a.d. VI Kal. Mart., the 25th day of February was a.d. VI Kal. Mart. and the 24th day was Bis a.d. VI Kal. Mart. (the second sixth day from the Kalends of March… of course, it precedes the first sixth day before since we are counting backward). Note "second sixth" hence the alternate name for leap year: "bissextile year".

In the Middle Ages, they kept the Roman numbering of days, so what we now call the 24th of February really was the leap day. Even after modern day-of-month notation came into vogue, the Catholic Church kept feast days that were on 24-28 February in normal years shifted by one day to 25-29 February in leap years, and this was not generally changed until 1970.

Note that saying Terminalia was the last day of the Roman sacred year does not mean that the next day was the first day of the new year. The sacred new year really did start on March 1 (as opposed to the political new year which had been January 1 since the mid-2nd century BC). But the last 5 days of February were the precursor to the new year celebration, and not part of the previous year. That's why intercalary months cut February short by 5 days (and then the entire intercalary month was a run-up to the new year with the festivals that precede the new year being celebrated on its last five days).


Take the Leap: Why 2020’s Leap Day Is Crowded With Weddings

Leap Year comes but once every four years. And Leap Day, February 29, is not a national holiday anywhere. But that doesn’t stop the special day from being a highly coveted date for marrying couples to set their weddings on. Even better, this year’s Leap Day falls on a Saturday (last time it fell on a Monday), which provides just one more reason for a full-fledged celebration.

A small chapel in Las Vegas, for example, has more than 70 weddings and vow renewal ceremonies scheduled for Saturday alone. “We wanted to do something truly epic for Leap Day, especially since it falls on a Saturday,” Donne Kerestic, CEO of the chapel in question, Chapel of the Flowers, said in a press release this week announcing a skydiving contest called “Take the Leap Day Wedding Contest” in the spirit of the special day.

Elsewhere, Zola, a New York-based online wedding registry, has seen a spike in couples who plan to tie the knot this February.

“Couples love any date that includes a special pattern or significance,” Jennifer Spector, Zola’s director of brand, told Observer. “ Choosing a date with a special pattern or holiday means your partner has literally no excuse to forget your anniversary.”

“This year, February is a particularly popular month to get married because it’s full of special dates like 02/02/20 and 02/22/20,” Spector added. “Valentine’s Day is also becoming an increasingly popular wedding date, especially because it fell on a Friday this year.”

Zola has seen a surge in demand for winter-themed decorations, such as feathers, jewel-toned bridesmaid dresses and romantic lighting, from couples who’ve had their big day in February, Spector said.

The origin of Leap Day dates back to approximately 2,000 years ago when ancient Roman leader Julius Caesar introduced it to the calendar to balance out the small discrepancy between the 365-day solar calendar and the Earth’s actual orbit time around the sun.


45 B.C.: The first Leap Day is recognized by proclamation of Julius Caesar.

In 45 B.C., Julius Caesar was attempting to develop a 365-day calendar when he confronted a slight dilemma: The earth's orbit around the sun takes about 365 days and six hours, which would make the calendar year slightly shorter than the solar year. Not taking this into account would throw off the passage of time and changing seasons.

To remedy this, Caesar recruited an Alexandrian astronomer named Sosigenes, and together they decided to add an extra day to the calendar every four years. Though the idea seemed simple at first, after a few centuries, it was clear something was off.

Their calculations were slightly wrong. The solar year was actually a bit shorter than they had thought. So rather than catching up, the calendar was speeding ahead.

By the end of the 16th century, the calendar year had sped as much as 10 days ahead.

The introduction of the Gregorian calendar in 1582 marked the Western calendar as we now know it. The current calculation of a solar year is 365.2425 days, and though our leap year situation is still not perfect, it will be off by about one day only every 3,030 years.


3. The Salem witchcraft trials are connected to Leap Day

If we’re looking at history a bit closer to home in the United States, then we should focus on Massachusetts. The Salem witchcraft trials weren’t a fun time in colonial America. There was a particularly negative connection with Leap Day. The first warrants for arrest went out on February 29th, 1692 for the Salem witchcraft trials. And you thought Friday the 13th was spooky! Find out some strange things that really happened on Friday the 13th.


Why Is There a Leap Day Every Four Years? Here’s the Science Behind Feb. 29th

Photo via Instagram / @forttwo42

The last leap year was Feb. 29, 2016, which means we won’t have another one until 2020. However, most people don’t know why we periodically add the 29th day of February.

The easy answer? Leap year is a corrective measure for our calendar system. However, the concept is so much more detailed than that.

ENTITY wants to make it easy for you.

First things first, why is there a leap day?

When it comes to answering this question, you should know that leap year is much more than a fun day – February 29th – that gets added every four years. Leap year actually has a scientific purpose to keep our calendars aligned with the solar year.

The concept arose in Rome while Julius Caesar was in power. While he toyed with the idea of adding a leap month to compensate for calendar shifts, top astronomers at the time advised him otherwise.

They explained that his calculation was based on a year having 364 days, but in reality it has 365.25 days. With this new information, the leap year concept transformed from Caesar’s 15-month calendar to adding a single leap day on Feb. 24 in 45 B.C.

However, their estimates were also slightly off because a year is actually 11 minutes short of 365.25 days. To be exact, a single year is 365 days, five hours, 48 minutes and 46 seconds.

Interestingly enough, this distinction led to some pretty weird leap year rules when it comes to the turn of the century. By 1582, the previous astronomer method caused the calendar to be 10 days off, notable by Easter occurring too late in Spring. Pope Gregory XIII then amended Caesar’s calendar by creating a system that subtracts three leap years every 400 years.

This compensated for history’s earlier mistake.

In the new system, if the turn of the century year is divisible by 400, a leap year occurs. Likewise, if a century year is not divisible by 400, there is not a leap year for another four years. Simply said, the year 2000 is divisible by 400, so a leap year occurred. The year 1700 is not, so the leap year was skipped for an additional four years.

Here’s the science behind leap year.

Let’s start with what we know already. A single year is 365 days, five hours, 48 minutes and 46 seconds. That almost quarter of a day tacked on to the 365 days is the important concept when it comes to answering, “What is leap year?”

We still use the Gregorian calendar today, so we discount the extra five hours, 48 minutes and 46 seconds. Easier said, we have 365 days in a standard calendar year. But, that doesn’t mean the quarter of a day we don’t factor in just magically disappears. Every four years, those five hours, 48 minutes and 46 seconds add up to a single day.

That’s where the concept of the leap year occurring every four years comes into play. We are essentially giving the fourth year 366 days to account for the time we take out in a standard year.

Why does this matter?

So you may be asking, “Why does it matter if we count the extra time every year or every four years?” Aside from avoiding an awkward New Year’s celebration a quarter into the last day of the year, there are real issues relating to early sustainability and time that a leap year reconciles.

This goes back to the concept of our calendars being aligned with the solar year. Our system relies on the sun to dictate how many days make up a year and when the seasons begin. When it comes to determining seasons, scientists observe the sun’s position on the horizon. It moves further south in the winter season and north in the summer.

In the early days, the leap year helped farmers account for seasonal switches that would affect crop growth. Today, it sets our concept of time that helps us accurately and efficiently predict future events.

For example, a 365 day calendar that discounts those five hours, 48 minutes and 46 seconds without adding a leap year, would provide a whole new concept of the seasons as time passes. After 750 years, June would be observed in winter instead of summer.

This means there would be no more “white Christmas” or springtime Easter celebrations. In addition to the predictability of future planning increasing with a leap year, socio-cultural reasons like holidays have pushed the system to continue.

But, why do we always add a day to February?

We’re heading back to ancient Rome when it comes to this portion of the what is leap year question.

February is shorter than the other months. While a popular circulating myth attributes the shortened month to Augustus Caesar stealing a day from February to give his month, August, a 31st day, this explanation is just another tall tale of the Internet.

In reality, February is shorter because it was an afterthought in the traditional Roman calendar.

In 8th century B.C., the Roman calendar had 10 months, starting in March. This meant January and February didn’t exist. They also did not account for the 31st day in their month Sextilis, equivalent to August, and December.

Why did the Romans ignore 61 days of the year? The cold days January and February are known for, aren’t productive to crop growth. At this time, crop growth and seasonal habits were the whole point of having a calendar and they didn’t see the need to consider the first two months.

However, through time and superstition, the cold months were added to the calendar.

Picking a leap day depends on culture.

Calendar days were changed to alternating odd numbers – 29 days or 31 days in 713 B.C. – and were based on a lunar rather than a solar system. February was left the oddball out with 28 days because back then it was considered the last month, not the second.

By the time Caesar stepped in with the solar year system, February was now considered at the beginning of the calendar. Withstanding the changes, it kept its 28 days. Then, February finally stopped getting the short end of the stick, which brings us back to the Romans creating the leap day on Feb. 24.

In the modern world, switching the day to the end of the month was just more practical and convenient. Although, some countries still have not adopted the Gregorian calendar. China, for example, includes a leap month. Meanwhile, Iran does not recognize Feb. 29 as a leap day and instead calculates leap years by seasonal equinoxes instead of mathematics.

So now you know everything you need to know about the leap year. It’s time to spread your newfound knowledge and share this article with your friends!


Leap Day Superstitions: What You Should and Shouldn’t Do on Feb. 29

Photo via Instagram / @bezyphoto

Leap Day occurs every four years on Feb. 29, with the next one coming up in 2020. While the scientific significance of Leap Day is to keep the Gregorian calendar in line with the solar year, thus keeping the future predictable, cultures have different perspectives on the holiday. This definitely leads to some interesting Leap Day superstitions.

ENTITY compiled a list of the most popular Leap Day superstitions.

The Irish think Leap Day is good luck.

In Ireland, Feb. 29 traditions play into Leap Day superstitions. It is believed that the day brings good luck.

Because of this, women are encouraged to propose to their boyfriends on Leap Day. The legend dates back to the fifth century when Saint Brigid of Kildare allegedly proposed to Saint Patrick after convincing him to allow women to propose to their timid male suitors once every four years.

As legend has it, Saint Patrick turned her down, but gave her a silk gown as compensation.

The legend has been debunked by historians because Saint Brigid of Kildare was only nine when Saint Patrick died, making the tale highly unlikely.

Nevertheless, the Irish still consider Leap Day lucky and keep the tradition of women proposing on Feb. 29 alive.

But other Europeans consider it bad luck.

However, some Europeans hold Leap Day superstitions that Feb. 29 brings bad luck. Such cases can be seen in Scotland, Greece and Italy.

In Scotland, the legend dates back to 1288 when Queen Margaret allegedly enacted a law allowing women to propose on Leap Day if they wore a red petticoat to warn her suitor of a proposal. This legend was also debunked because Queen Margaret was only five-years-old when the law was enacted. In fact, historians have trouble finding any evidence that the law ever existed at all.

The Greeks also consider Leap Day and the entire year to be bad luck, specifically when it comes to marriage. Because of this, engaged couples will wait until leap year passes to say their vows.

Like the Greeks, in Italy, Leap Day superstitions advise against buying a house or a car and waiting until the next year to avoid bad luck.

Multiple countries also consider having a child during leap year bad luck and say the child will be difficult to raise.

There is also a spiritual significance to leap year.

When it comes to Leap Day superstitions, the spiritual community sees Feb. 29 in a positive light. They believe the day is good for healing, learning and love.

They also think it is a time to follow your soul’s innermost desires and ambitions.

This is has to do with the numerology behind the date Feb. 29. Both the numbers two and 11 (2+9) have these special meanings in the spiritual community.

How are Leap Day and death related?

Among Leap Day superstitions, another common claim is that Leap Day brings more death. While they seem to be focusing on a perceived mystical aspect behind this claim, there is a legitimate scientific reason for more death.

We add a day, meaning there are 24 more hours available for people to kick the bucket. Morbid, we know. But, this would definitely explain why people think leap year brings more death.

So whether you buy into the Leap Day superstitions or not, at least you’ll have some fun facts to share with your friends in February 2020.


Leap Year Superstitions

Our everyday calendar is an artificial medium that has been juggled with through the centuries in an effort to make it more accurate and more useful. The time it takes for the earth to rotate is 365 ¼ days but the calendar year is 365 days, hence once every four years to balance this, we have a leap year and an extra day, February 29th.

Because such years are rarer than normal years, they have become lucky omens. Indeed the 29th February itself is an especially important day. Anything started on this day is sure of success.

Certainly February 29th in the leap year of 1504 was very successful for one Christopher Columbus.

The famous explorer had been marooned for several months on the small island of Jamaica. Though the island natives had initially offered food and provisions, Columbus’ arrogant and overbearing attitude had so annoyed the natives that they stopped this altogether.

Facing starvation, Columbus came up with an inspired plan. Consulting a shipboard almanac and finding that a lunar eclipse was due, he called together the native chiefs and announced to them that God would punish them if they did not supply his crew with food. And as an omen of God’s intent to punish them, there would be a sign in the sky: God would darken the Moon.

Right on cue, the lunar eclipse started. Columbus dramatically disappeared into his cabin as the natives began to panic and begged him to restore the Moon. After more than an hour, Columbus emerged from his cabin and announced that God was prepared to withdraw his punishment if the natives agreed to supply him and his crew with everything they needed. The native chiefs immediately agreed, and within minutes the Moon started emerging from shadow, leaving the natives in awe of Columbus’ power. Columbus continued to receive food and supplies until he was rescued in June 1504.

For women, February 29th can also be a very successful day, as once every four years on the 29th February they have the “right” to propose to a man.

The right of every women to propose on 29th February each leap year goes back hundreds of years when the leap year day had no recognition in English law (the day was ‘leapt over’ and ignored, hence the term ‘leap year’). It was decided that the day had no legal status, meaning that a break in tradition on this day was acceptable.

So on this day, women can take advantage of this anomaly and propose to the man they wish to marry.

In Scotland however, to ensure success they should also wear a red petticoat under their dress – and make sure that it is partly visible to the man when they propose.

For those wishing to take advantage of this ancient tradition, 29th February is your day!


Julius Caesar, Father of Leap Year

Julius Caesar was behind the origin of leap year in 45 BCE. The early Romans had a 355-day calendar and to keep festivals occurring around the same season each year, a 22- or 23-day month was created every second year. Julius Caesar decided to simplify things and added days to different months of the year to create the 365-day calendar the actual calculations were made by Caesar's astronomer, Sosigenes. Every fourth year following the 28th day of Februarius (February 29) one day was to be added, making every fourth year a leap year.

In 1582, Pope Gregory XIII further refined the calendar with the rule that leap day would occur in any year divisible by four as described previously.


Leap Day, 1992

Going back far into the history of video games, there's not much to say about leap day. The only release that occurred on the leap day of 1992 was Shanghai II: Dragon's Eye on the X68000. The X68000 was a home computer released by Sharp Corporation in 1987, and had a few games developed for it such as Castlevania Chronicles and Prince of Persia. Shanghai II: Dragon's Eye, the game which celebrates its seventh birthday today, was essentially a Mahjong simulator developed by Activision.


A few facts about leap day

February 29 can seem like a mysterious thing. But why it happens every four years is actually very simple. So simple, we can explain it in just 30 seconds.

A homemade February 2016 calendar illustrating leap year. Feb. 29 is that extra day that rolls around every four years. (Photo: Leanne Italie, AP)

Surrounded in history and superstition, February 29 only comes once every four years— and we have one Monday. Here are a few facts about leap day.

Bachelor’s Day

In Ireland, February 29 is Bachelor's Day - a traditional holiday when women propose to men. Scotland began the tradition in 1288 by passing a law permitting women to propose and if refused, the man had to pay a fine. Now, the tradition is just an amusing historical tidbit.

2. Gregorian calendar roots

Pope Paul III, the last of the Renaissance popes, was born on a leap day in 1468. Interestingly enough, it was another pope who established the Gregorian calendar - Pope Gregory XIII.

Julius Caesar introduced the idea, but the math he used wasn't quite right, creating too many leap years. Essentially, every 400 years, we ended up with three extra days, so to compensate, centuries must be divisible by 400 to count as leap years. Years like 1700, 1800 and 1900 are only 365 days long, rather than 366.

Leap day babies

The chances of having a birthday on a leap day are about one in 1,461, according to BBC.

Leap year babies, called leaplings, are said to have unusual talents by astrologers.

Two women have given birth to three leap day babies, according to the New York Daily News. The Henriksen family from Norway had their children on leap days in 1960, 1964 and 1968. The most recent family to tie the record is the Estes family from Utah. Their children were born in 2004, 2008 and 2012. So, depending on how you look at it, the children will celebrate their third, second and first birthdays this year.

Even more rare, the eighth premier of Tasmania, James Milne Wilson, was born on a leap day and died on a leap day in the 1800s, according to the World Heritage Encyclopedia.

Kathie Taylor may be close to 100, but this leap year baby is just now celebrating her 24th birthday. She was born on February 29, 1920.

February 29 in history

In order to gain the cooperation of the indigenous people of Jamaica, Christopher Columbus used the lunar eclipseon February 29, 1504, to his advantage, according to the BBC. The local chiefs decided to stop helping his crew with the food and provisions they had been supplying, so he told them that God was going to punish them by painting the moon red. During the eclipse, Columbus said God would end the punishment if they cooperated. The chiefs agreed to continue giving them supplies, and of course the lunar eclipse ended.

The first warrants of the Salem witch trials were issued on February 29, 1692. The trials continued until early 1693 and resulted in the execution of 20 people and the death of seven others in jail, History.com reported.

On February 29, 1940, Hattie McDaniel became the first black woman to win an Oscar, according to History.com. She was awarded for her role in Gone With the Wind.

Leap Year: Special travel deals for leap day babies and more this Feb. 29