When is the leap year. Leap year is not terrible

A leap year occurs once every four years. But why then was 1904 a leap year, 1900 was not, and 2000 was again?

In a leap year, the Summer Olympics are held - where did this order come from? And why do we need any special "extended" years? How are they different from normal ones? Let's figure it out.

Who introduced leap years into the calendar?

Ancient Roman astronomers were well aware that a year on Earth lasts 365 days and a few more hours. Because of this, the calendar year, which then consisted of a constant number of days, did not coincide with the astronomical one. The surplus of hours gradually accumulated, turning into days. Calendar dates gradually shifted and deviated from natural phenomena - for example, the equinoxes. A group of astronomers led by Sosigenes, who worked at the court of Julius Caesar, proposed to correct the calendar. According to the new chronology, every fourth year was extended by one day. This year is called bis sextus which in Latin means "second sixth" . In Russian, this word has been transformed into "leap year" That's what we call it to this day.

By order of Julius Caesar, a new calendar was introduced starting from the year 45 BC. After the death of the emperor, there was a failure in the calculation of leap years, and the countdown began again from the 8th year of our era. Therefore, in our time, even years are leap years.

It was decided to add a day to the last, shortest month of the year, which already "did not have enough days." In ancient Rome, the New Year was celebrated on March 1, so an extra 366th day was added to February. The new calendar began to be called "Julian" in honor of Caesar. By the way, the Orthodox and some other churches still live according to the Julian calendar - this is a tribute to tradition.

And again the calendar changes

Astronomical observations continued, methods became more and more accurate. Over time, astrologers realized that the duration of the earth's year is not 365 days and 6 hours, but a little less. (It is now known that a year lasts 365 days 5 hours 48 minutes and 46 seconds).


The use of the Julian chronology led to the fact that the calendar began to be late from the real flow of time. Astronomers have noticed that the spring equinox occurs much earlier than the day allotted for it according to the calendar, that is, March 21. There was a need to correct the calendar, which was done by decree of Pope Gregory XIII in 1582.

To compensate for the discrepancy, we decided to set leap years according to a new rule. It was necessary to reduce their number, which was done. From that moment on, all years divisible by 4, except those that are divisible by 100, are still considered leap years. For even more accurate chronology, years that are divisible by 400 are still considered leap years.

This is why 1900 (like 1700 and 1800) was not a leap year, but 2000 (like 1600) was.

The new calendar was named in honor of the Pope Gregorian - it is currently used by all countries of the world. The Julian calendar is used by a number of Christian churches, including the Russian Orthodox Church.

Rule for determining leap years

So, leap years are determined by a simple algorithm:

If a year is divisible by 4 but not divisible by 100, it is a leap year;

If a year is divisible by 100, it is not considered a leap year;

If a year is divisible by 100 and also by 400, it is a leap year.

How is a leap year different from others?

Only one - it has 366 days, and an additional day is assigned to February. Despite the fact that the year now starts on January 1, which means that the last month of the year is December, we still give an extra day to February. He is the shortest - we will regret him!

And we will rejoice for those who were born on February 29 in a leap year. These "lucky ones" celebrate their birthday every four years, which makes this event more long-awaited and desired than other people.

What happens in a leap year?

Leap years were chosen to host the main sporting event of mankind - the Olympics. Now, in leap years, only the Summer Games are held, and the Winter Games are held with a two-year shift. The sports community adheres to the oldest tradition, which was established by the first Olympians - the ancient Greeks.


It was they who decided that such a grandiose event should not take place too often - once every four years. The four-year cycle coincided with the alternation of leap years, so the modern Olympics began to be held in leap years.

Leap year (lat. bis sextus - “second sixth”) - a year in the Julian and Gregorian calendars, the duration of which is 366 days - one day more than the duration of a regular, non-leap year. In the Julian calendar, a leap year is every fourth year; in the Gregorian calendar, there are exceptions to this rule.

A year is a conventional unit of time, which historically meant a single cycle of seasons (spring, summer, autumn, winter). In most countries, the calendar length of the year is 365 or 366 days. At present, the year is also used as a temporal characteristic of the revolution of planets around stars in planetary systems, in particular the Earth around the Sun.

The calendar year in the Gregorian and Julian calendars is 365 days in non-leap years and 366 days in leap years. The average length of the year is 365.2425 days for the Gregorian and 365.25 days for the Julian calendar.

The calendar year in the Islamic calendar contains 353, 354 or 355 days - 12 lunar months. The average length of the year is 354.37 days, which is less than the tropical year, and therefore Muslim holidays "roam" according to the seasons.

The calendar year in the Jewish calendar contains 353, 354 or 355 days in a simple year and 383, 384 or 385 days in a leap year. The average length of the year is 365.2468 days, which is close to the tropical year.

The length of the tropical year (the time between the two vernal equinoxes) is 365 days 5 hours 48 minutes 46 seconds. The difference in the duration of the tropical year and the average Julian calendar year (365.25 days) is 11 minutes 14 seconds. Of these 11 minutes and 14 seconds, approximately 128 years add up to one day.

As the centuries passed, a shift in the day of the vernal equinox, with which church holidays are associated, was noticed. By the 16th century, the vernal equinox occurred about 10 days earlier than March 21, which is used to determine the day of Easter.

To compensate for the accumulated error and avoid such a shift in the future, in 1582, Pope Gregory XIII reformed the calendar. In order to better match the average calendar year to the solar year, it was decided to change the leap year rule. As before, a year remained a leap year, the number of which is a multiple of four, but an exception was made for those that were a multiple of 100. From now on, such years were leap years only when they were also divided by 400.

In other words, a year is a leap year in two cases: either it is a multiple of 4, but not a multiple of 100, or it is a multiple of 400. A year is not a leap year if it is not a multiple of 4, or it is a multiple of 100, but not a multiple of 400.

The last years of centuries ending in two zeros are not leap years in three cases out of four. So, the years 1700, 1800 and 1900 are not leap years, since they are a multiple of 100 and not a multiple of 400. The years 1600 and 2000 are leap years, since they are a multiple of 400. The years 2100, 2200 and 2300 are non-leap years. In leap years, an extra day is introduced - February 29. The Catholic world lives according to the Julian calendar. Unlike the Julian calendar, the Gregorian calendar takes into account only one object - the Sun.

Now we live according to the Julian calendar (new style), before the revolution we lived according to the Gregorian (old style). The difference between the old and new styles was 11 days in the 18th century, 12 days in the 19th century, and 13 days in the 20th-21st centuries. In the 22nd century, this difference will already be 14 days. The Gregorian calendar was introduced under Soviet rule on February 14, 1918 (after January 31, it was no longer February 1, but immediately the 14th). The last leap year was , the next one will be .

1996, 1992, 1988, 1984, 1980, 1976, 1972, 1968, 1964, 1960, 1956, 1952, 1948, 1944, 1940, 1936, 1932, 1928, 1924, 1920, 1916, 1912, 1908, 1904, according to Gregorian 1900 is a non-leap year, Julian is a leap year. 1896.

Note: For most computer and mobile systems, valid dates are from December 13, 1901, 20:45:54 GMT to January 19, 2038, 03:14:07 GMT. (These dates correspond to the minimum and maximum value of a 32-bit signed integer). For Windows, valid dates are from 01-01-1970 to 01-19-2038.

Undoubtedly, almost everyone knows that usually a year has 365 days, but a leap year is longer by a whole day. People believe that a leap year brings great sorrows, tragedies, illnesses, big and small troubles. Some call this thinking superstition, while others firmly believe in an "unlucky" year.

At present, our lives are already filled with horrors and fears that seem to lurk around every corner, so people are asking in advance - Is 2017 a leap year or not? We will be happy to answer the burning question and tell you a little about the leap year itself.

Is 2017 a leap year?

No, not a leap year, as it only has 365 days. But 2016, which is already beginning to come to an end, is just that. The Year of the Monkey turned out to be difficult, there were all sorts of things - both floods and various disasters, both local and general.

No wonder people say that a leap year brings bad luck. For years, centuries, people have watched the events taking place, thanks to which the leap year has bothered to be called an unfavorable year.

How to determine if it's a leap year or not

In fact, everything is not as difficult as it seems at first glance. Someone simply remembers which year is a leap year and counts four years, because it is with such a frequency that a “leap year” occurs - for every fourth year.

But what if you completely forgot - when was the leap year and you urgently need to determine the number of days of the next year - 365 or 366?

In this case, there are three simple rules, thanks to which you can easily calculate what year is now or will be sometime later.

1. A certain year with zeros at the end is a leap year when it is divisible without a remainder by both "4", and "100", and "400". For example, 2000/4=500; 2000/100=20; 2000/400=5. But the years 1800 and 1900 are not leap years, and also they are not a multiple of "400", but a multiple of "4" and "100".
2. If a certain year is divisible by "4" without a remainder, then it is a leap year. For example, 2016/4=504; 2020/4=505 etc.
3. If a certain year is divisible without a remainder by 4, 100, and 1000, then it is a leap year. For example, 2000/1000=2.

These rules were formulated by none other than the creator of the Gregorian calendar, Pope Gregory XIII back in 1582.

The history of the occurrence of such a phenomenon as a leap year

Back in 45 BC. Alexandrian astrologers, on the orders of Julius Caesar, developed the Julian, according to which, the astronomical year contained 365 days and 6 hours. That's just in order to somehow align the shift in time, and introduced the concept of a leap year. For three years, the usual calculation of 365 days went on, and in the fourth year, February added one more to its 28 days. Why February? The answer is simple - in the Roman Empire, February was considered the final month of the year.

So, February 29 began to appear in calendars with a frequency of 4 years. Two years after the introduction of the leap year, Julius Caesar died in an unequal battle with traitors. The priests, apparently, misunderstood the calendar created by the Roman dictator, and for 36 years after the death of Caesar, the leap year came not every four, but every three years. Emperor Augustus succeeded in restoring order.

Popular beliefs in a leap year

Translated from Latin, the leap year is translated as "the second sixth." The duration of bis sextus is 366 days. The “added” day scares people, which creates a whole superstition around every fourth year.

Rumor has it that February 29 is the most difficult and difficult day in terms of health. This extra day is called the day of Kasyan and is considered demonic. If you work on this day, then nothing will come of it. They also try not to go outside again, otherwise the risk of sudden death increases. Even newborn babies, who are “unfortunate” to be born on this day, are expected by superstitions that “kind” people will invest in a child’s head from infancy. According to ancient beliefs, those born on February 29 will be seriously ill and leave our world early.

The most common superstition associated with a leap year is marriage. Mothers strictly forbid their children to marry in this "terrible" year. A marriage made on a leap year is doomed to be unhappy. This is how they think, mainly in villages and villages.

It is also impossible to radically change something in your life. Under the ban, moving, changing jobs, even a pet is better not to start. In a word, it is better to postpone any changes until better times.

If we believe the observations of our ancestors, then the leap year will only bring big declines, small and grandiose problems. We need to be as careful and prudent as possible this year. Pregnant women should not cut their hair, young people should not be caroled, no one should be told about plans for the future, and much, much more. Even divorce in a leap year is undesirable.

Someone follows all the beliefs and is actually afraid of a leap year. Others are more optimistic about the future. They are sure that once they have lived to see a leap year, this is already good, and they wish everyone a great many more leap years.

A leap year, or it is also called the word "leap year", causes a lot of rumors and superstitions, which boil down mainly to the fact that this year is unhappy and promises only one negative event. In this article, we will discuss how true these opinions are.

A bit of history

The word "leap" came to us from the Latin language, that is, it is of ancient origin, and its literal translation sounds like "second sixth".

According to the Julian calendar, the Earth goes through its cycle in 365.25 days, while every year the day shifted by 6 hours. Such an error could well confuse ancient men, and in order to avoid this, it was decided that after every fourth year another day would be added to the annual cycle. Accordingly, this year will include 366 days, and they will be added in the shortest month - February, it will consist of 29 days. For distinction, he was called a leap.

In Ancient Russia, in turn, there were many legends about the emergence of leap years, and each of them was already perceived as necessarily unlucky. The legends about the arrival of the new calendar and the leap year in it in Russia were also reflected in the Saints. So, February 29 is dedicated to the memory of St. Kasyan, and among the people he is called Kasyanov Day. Several legends and apocrypha are dedicated to this day (stories that are not recognized by the church as confirmed and consistent with what we know about God). But it sheds light on the origin of the bad reputation of the leaps.

According to this legend, Kasyan appears to the common people not as a man, but as an angel, moreover, a fallen one, who was once tempted by Satan, as a result of which he fell away from God. However, in the future, he realized how wrong he was, repented and begged the Creator for mercy. Taking pity on the traitor, God, before taking him back, put His angel to him. The celestial shackled Kasyan and, by order from above, beat him on the forehead with a metal hammer for admonition for 3 years, and released him on the fourth.

The second legend about Kasyan

According to the second story Kasyan- this is a person, and Kasyanov's day is the date of his name day. However, according to legend, that man systematically drunk dead for three years in a row, but on the fourth he came to his senses, brought repentance, gave up addiction, turned to repentance and became a saint - he acquired the Holy Spirit. Therefore, the people considered, it is fitting for them to celebrate their day so rarely - only on February 29th.

The third legend about Kasyan

This legend is dedicated to St. Kasyan traveling the earth and Nicholas the Wonderworker, well known to Christians. And then they meet a man along the way. He asked them for help as his wagon became bogged down in the mud. Kasyan replied to this that he was careful not to spoil his clean riza, and Nikolai, not afraid of dirt, immediately helped. The saints returned to the Kingdom of God, and the Creator noticed that Nikolai's robe was dirty and asked him what it was about.

The Saint told him what had happened on the way. Then the Lord noticed that Kasyan's clothes were clean, and asked the question: did they not travel together? Kasyan replied that he was afraid to stain his clothes. God understood that Cosmas was cunning, and arranged in such a way that his name day is celebrated with him once every 4 years. And Nikolai's namesake for his meekness - twice in 365 days.

Anyway , whatever it may be, the leap was recognized as bad. Therefore, the Russian superstitious people tried to somehow protect themselves from this day.

1. I tried to finish all the important things before the 29th of February.
2. Some did not dare to leave the house.
3. On February 29, if the sun came out, it was called Kasyan's Eye or Kasyanov's Eye. Then they tried not to fall under the sun, so that the saint would not… jinx them! And he did not bring suffering and disease to the poor person.

As in ancient times, in today's world, superstitions and omens often come across that do not define leap years of the 21st century from the best side. We list some of them:

Why is a leap year considered bad?

Such an attitude is quite understandable: the appearance of the 29th day in February characterizes the whole year differently from others, psychologically distinguishes it from among the others. This can be important for a person who is unsure of their abilities. It will be much easier for him, referring to this special period, to refuse something new than to expend energy for self-development or the start of some business.

For the same reason, it will be easier not to get pregnant, so as not to give birth later, because the fear that the birth will be difficult increases, the baby may be born painful. And if not, then suddenly his life will be bleak or hard.

See our resourceful people and the threat in the very name of the leap year, saying that it “mows down” people, in other words, takes them away, leads to death. Therefore, the holiday is met with apprehension (or, conversely, on a special scale - you never know who will die ...). This is a very common belief that tries to infiltrate the statistics. It is becoming accepted that the death rate increases every 4th year. At the same time, the statistics themselves do not confirm these data in any way.

Mushrooms can not be collected either, and even more so they can be eaten or sold to people. No, not so as not to get poisoned, but so that with the “bad earth” a person does not get “something bad”.

It is believed that a leap year entails cataclysms in nature and all sorts of disasters: drought, floods, fires.

What years are leap years

In the last century, as well as in the present, such calendar periods also terrified. A list of them can be seen in the image or found on the Internet. Also, the year 2000, the same millennium, in turn was a leap year, opening a whole millennium.

Despite the fact that with the development of technology, information has become more accessible and it has become possible to learn more and expand one's horizons, getting rid of primitive fears, many continue to anxiously expect a leap year, internally setting themselves up for problems and troubles, and when they come (if they come), this is perceived as doomed: well, it's a leap year... An extra day in February. Deadly!

There are special calendars that indicate exactly when the leap year occurs. It is enough to carefully look at the table and find (or not find) the actual numbers there. It is enough to know at least one leap year, after which, through elementary arithmetic, it will be possible to calculate them yourself. Let's say you're interested in leap years in the 21st century. Find a calendar and view it. Knowing that 2016 is a leap year, it is easy to understand that the next one will come in 2020.

If you trust the statistics, a very small number of all catastrophes and misfortunes falls on leap years. The superstitions that exist today can be interpreted by the fact that people who were closely following the misfortunes and misfortunes that occurred at leap years, communicated an exaggerated meaning to what was happening only because of the unflattering reputation of the latter. Persons who extremely trust superstitions about leap years would like to wish to pay more attention to positive events and changes. And then, perhaps, there will be a list of good and joyful signs restoring the reputation of the leaps.

sharky:
03/25/2013 at 16:04

and why is 1900 not a leap year? A leap year occurs every 4 years, i.e. Divisible by 4, it's a leap year. And no more divisions by 100 or 400.

Asking questions is normal, but before you say something, study the materiel. The earth revolves around the sun in 365 days 5 hours 48 minutes 46 seconds. As you can see, the rest is not exactly 6 hours, but 11 minutes 14 seconds less. This means that by making a leap year we add extra time. Somewhere in 128 years, extra days accumulate. Therefore, every 128 years in one of the 4-year cycles, a leap year is not necessary to get rid of these extra days. But to simplify, a leap year is not made every 100th year. Is the idea clear? Good. But how then to proceed, because an extra day is added every 128 years, and we cut it every 100 years? Yes, we cut off more than it should be, and this must be returned sometime.

If the first paragraph is clear and still interesting, then read on, but it will be more difficult.

So, in 100 years, 100/128=25/32 days of excess time accumulate (this is 18 hours 45 minutes). We do not make a leap year, that is, we subtract one day: we get 25/32-32/32 = -7/32 days (this is 5 hours and 15 minutes), that is, we subtract the excess. After four cycles of 100 years each (after 400 years) we will subtract an extra 4*(-7/32)=-28/32 days (this is minus 21 hours). On the 400th year, we make a leap year, that is, we add a day (24 hours): -28/32+32/32=4/32=1/8 (this is 3 hours).
We make every 4 years a leap year, but at the same time every 100 years is not a leap year and at the same time every 400 years is a leap year, but still every 400 years an extra 3 hours are added. After 8 cycles of 400 years, that is, after 3200 years, an extra 24 hours will accumulate, that is, one day. Then one more obligatory condition is added: every 3200th year should not be a leap year. 3200 years can be rounded up to 4000, but then again you have to play with added or truncated days.
3200 years have not passed, so this condition, if it is made so, is not yet spoken of. But 400 years have already passed since the approval of the Gregorian calendar.
Years divisible by 400 are always leap years (for now), other years divisible by 100 are not leap years, other years divisible by 4 are leap years.

My calculation shows that in the current state, an error of one day accumulates over 3200 years, but this is what Wikipedia writes about this:
“An error of one day compared to the year of the equinoxes in the Gregorian calendar will accumulate in about 10,000 years (in the Julian - in about 128 years). A frequently encountered estimate, leading to a value of the order of 3000 years, is obtained if we do not take into account that the number of days in a tropical year changes with time and, in addition, the ratio between the lengths of the seasons changes. From the same Wikipedia, the formula for the length of the year in days with fractions paints a good picture:

365,2425=365+0,25-0,01+0,0025=265+1/4-1/100+1/400

The year 1900 was not a leap year, but 2000 was, and special, because such a leap year happens once every 400 years.