A leap year (or intercalary year) is a year containing one or more extra days (or, in the case of lunisolar calendars, an extra month) in order to keep the calendar year synchronised with the astronomical or seasonal year. A lunisolar calendar is a Calendar in many Cultures whose date indicates both the Moon phase and the time of the solar Year. According to the Gregorian calendar, the calendar year begins on January 1 and ends on December 31. A year (from Old English gēr) is the time between two recurrences of an event related to the Orbit of the Earth around the Sun The seasonal year is the time between successive recurrences of a Seasonal event such as the flooding of a river the migration of a species of bird or the flowering of a species For example, in the Gregorian calendar, February has 29 days in a leap year instead of the usual 28 - and consequently, the year lasts 366 days instead of the common 365. The Gregorian calendar is the most widely used Calendar in the world today Because seasons and astronomical events do not repeat at an exact number of full days, a calendar that had the same number of days in each year would, over time, drift with respect to the event it was supposed to track. By occasionally inserting (or intercalating) an additional day or month into the year, the drift can be corrected. Intercalation is the insertion of a leap day week or month into some calendar years to make the calendar follow the seasons or moon phases A year that is not a leap year is called a common year. A common year is a common type of Calendar year. It has exactly 365 days and so is not a Leap year.

Gregorian calendar

In the Gregorian calendar, the current standard calendar in most of the world, most years whose division by 4 equals an integer are leap years. The Gregorian calendar is the most widely used Calendar in the world today In each leap year, the month of February has 29 days instead of 28. Adding an extra day to the calendar every four years compensates for the fact that a solar year is almost 6 hours longer than 365 days. A tropical year (also known as a solar year) is the length of time that the Sun takes to return to the same position in the cycle of seasons as seen from Earth

However, some exceptions to this rule are required since the duration of a solar year is slightly less than 365. 25 days. Years that are evenly divisible by 100 are not leap years, unless they are also evenly divisible by 400, in which case they are leap years. ^[1][2] For example, 1600 and 2000 were leap years, but 1700, 1800 and 1900 were not. Similarly, 2100, 2200, 2300, 2500, 2600, 2700, 2900, and 3000 will not be leap years, but 2400 and 2800 will be. By this rule, the average number of days per year will be 365 + 1/4 − 1/100 + 1/400 = 365. 2425, which is 365 days, 5 hours, 49 minutes, and 12 seconds.

The Gregorian calendar was designed to keep the vernal equinox on or close to March 21, so that the date of Easter (celebrated on the Sunday after the 14th day of the Moon (i. An equinox is the event of the Sun passing over the Earth's equator in its annual cycle Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem. Easter ( Greek: Πάσχα Pascha or Pasxa) is the most important religious feast in the Christian Liturgical year. e. a full moon) that falls on or after 21 March) remains correct with respect to the vernal equinox. Full moon is a Lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem. ^[3] The vernal equinox year is about 365. 242374 days long (and increasing), whereas the average year length of the Gregorian calendar is 365. 2425.

The marginal difference of 0. 000125 days means that in around 8,000 years, the calendar will be about one day behind where it is now. But in 8,000 years, the length of the vernal equinox year will have changed by an amount that cannot be accurately predicted (see below). Therefore, the current Gregorian calendar suffices for practical purposes, and Herschel's correction (making 4000 AD not a leap year) will probably not be necessary. Sir John Frederick William Herschel 1st Baronet KH, FRS ( March 7, 1792 &ndash May 11, 1871)was an

This graph shows the variation between the seasonal year versus the calendar year due to unequally spaced 'leap days' rules. See Iranian calendar to contrast with a calendar based on 8 leap days every 33 years. The Iranian calendar or Solar Hejri (تقویم هجری شمسی؛ سالنمای هجری خورشیدی Taqwim Hejri Shamsi Salanmay Hejri Khurshidi) is an astronomical

Algorithm

This algorithm determines leap years on the proleptic Gregorian calendar, which includes leap years before the official inception in 1582. The proleptic Gregorian calendar is produced by extending the Gregorian calendar backward to dates preceding its official introduction in 1582.

Pseudocode to determine whether a year is a leap year or not:

if year modulo 400 is 0 then leap else if year modulo 100 is 0 then no_leap else if year modulo 4 is 0 then leap else no_leap

A more direct algorithm (terms may be grouped either way):

if ((year modulo 4 is 0) and (year modulo 100 is not 0)) or (year modulo 400 is 0) then leap else no_leap

Leap day

Main article: February 29

February 29 is a date that usually occurs every four years, and is called leap day. Pseudocode is a compact and informal high-level description of a Computer programming Algorithm that uses the structural conventions of some Programming language Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours This day is added to the calendar in leap years as a corrective measure, because the earth does not orbit around the sun in precisely 365 days.

The Gregorian calendar is a modification of the Julian calendar first used by the Romans. The Julian calendar, a reform of the Roman calendar, was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 Ab urbe condita The Roman calendar originated as a lunisolar calendar and named many of its days after the syzygies of the moon: the new moon (Kalendae or calends, hence "calendar") and the full moon (Idus or ides). The Roman calendar changed its form several times in the time between the foundation of Rome and the fall of the Roman Empire. A lunisolar calendar is a Calendar in many Cultures whose date indicates both the Moon phase and the time of the solar Year. In broadest terms Syzygy (ˈsɪzɪʤi is a kind of unity especially through coordination or alignment most commonly used in the Astronomical and/or Astrological Full moon is a Lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. The Nonae or nones was not the first quarter moon but was exactly one nundinae or Roman market week of nine days before the ides, inclusively counting the ides as the first of those nine days. Lunar phase (or Moon phase refers to the appearance of the illuminated portion of the Moon as seen by an observer usually on Earth In 1825, Ideler believed that the lunisolar calendar was abandoned about 450 BC by the decemvirs, who implemented the Roman Republican calendar, used until 46 BC. Christian Ludwig Ideler ( September 21, 1766 &ndash August 10, 1846) German Chronologist and Astronomer, was Events By place Greece Athenian General Cimon sails to Cyprus with two hundred Triremes of the Decemviri (singular decemvir) is a Latin term meaning "Ten Men" which designates any such commission in the Roman Republic (cf The Roman calendar changed its form several times in the time between the foundation of Rome and the fall of the Roman Empire. The days of these calendars were counted down (inclusively) to the next named day, so 24 February was ante diem sextum Kalendas Martii ("the sixth day before the calends of March") often abbreviated a. Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the d. VI Kal. Mar. The Romans counted days inclusively in their calendars, so this was actually the fifth day before March 1 when counted in the modern exclusive manner (not including the starting day). Ancient Rome was a Civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC Events 86 BC - Lucius Cornelius Sulla, at the head of a Roman Republic army enters in Athens, removing the Tyrant ^[4]

The Republican calendar's intercalary month was inserted on the first or second day after the Terminalia (a. In Roman religion, Terminus was the god who protected Boundary markers his name was the Latin word for such a marker d. VII Kal. Mar. , February 23). Events 1455 - Traditional date for the publication of the Gutenberg Bible, the first Western Book printed from Movable The remaining days of Februarius were dropped. This intercalary month, named Intercalaris or Mercedonius, contained 27 days. Mercedonius, also known as Intercalaris, was the Intercalary month added in Leap years of the Roman calendar. The religious festivals that were normally celebrated in the last five days of February were moved to the last five days of Intercalaris. Because only 22 or 23 days were effectively added, not a full lunation, the calends and ides of the Roman Republican calendar were no longer associated with the new moon and full moon.

The Julian calendar, which was developed in 46 BC by Julius Caesar, and became effective in 45 BC, distributed an extra ten days among the months of the Roman Republican calendar. The Julian calendar, a reform of the Roman calendar, was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 Ab urbe condita Year 46 BC was the last year of the pre-Julian calendar. This year had 445 days due to the errors that had accumulated in the pre-Julian calendar Year 45 BC was the year the Julian calendar went into effect According to this calendar it was a Leap year starting on Friday (link will display the full calendar Caesar also replaced the intercalary month by a single intercalary day, located where the intercalary month used to be. To create the intercalary day, the existing ante diem sextum Kalendas Martii (February 24) was doubled, producing ante diem bis sextum Kalendas Martii. Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the Hence, the year containing the doubled day was a bissextile (bis sextum, "twice sixth") year. For legal purposes, the two days of the bis sextum were considered to be a single day, with the second half being intercalated, but common practice by 238, when Censorinus wrote, was that the intercalary day was followed by the last five days of February, a. Censorinus, Roman Grammarian and miscellaneous writer flourished during the 3rd century AD. d. VI, V, IV, III and pridie Kal. Mar. (which would be those days numbered 24, 25, 26, 27, and 28 from the beginning of February in a common year), i. e. the intercalated day was the first half of the doubled day. All later writers, including Macrobius about 430, Bede in 725, and other medieval computists (calculators of Easter), continued to state that the bissextum (bissextile day) occurred before the last five days of February. This article is about Macrobius the author for Macrobius the bishop of Seleucia and Calycadnum see Macrobius of Seleucia Ambrosius Theodosius Macrobius Bede (ˈbiːd (also Saint Bede, the Venerable Bede, or (from Latin Beda (beda (c Computus ( Latin for Computation) is the Calculation of the date of Easter in the Christian calendar. Easter ( Greek: Πάσχα Pascha or Pasxa) is the most important religious feast in the Christian Liturgical year.

Until 1970, the Roman Catholic Church always celebrated the feast of Saint Matthias on a. In the New Testament Acts of the Apostles, the author of the Gospel of Luke records that Saint Matthias was the Apostle chosen by the remaining d. VI Kal. Mar. , so if the days were numbered from the beginning of the month, it was named February 24 in common years, but the presence of the bissextum in a bissextile year immediately before a. Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the d. VI Kal. Mar. shifted the latter day to February 25 in leap years, with the Vigil of St. Events 138 - The Emperor Hadrian adopts Antoninus Pius, effectively making him his successor Pettie The Vigiljpg|right|thumb|200px|"A Knight's Vigil" by John Pettie]] A vigil (from the Latin vigilia, meaning wakefulness) is Matthias shifting from February 23 to the leap day of February 24. Events 1455 - Traditional date for the publication of the Gutenberg Bible, the first Western Book printed from Movable Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the Other feasts normally falling on February 25–28 in common years are also shifted to the following day in a leap year (although they would be on the same day according to the Roman notation). The practice is still observed by those who use the older calendars.

Julian, Coptic and Ethiopian calendars

The Julian calendar adds an extra day to February in years evenly divisible by four. The Julian calendar, a reform of the Roman calendar, was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 Ab urbe condita

The Coptic calendar and Ethiopian calendar also add an extra day to the end of the year once every four years before a Julian 29-day February. The Coptic calendar, also called the Alexandrian calendar, is used by the Coptic Orthodox Church and still used in Egypt The Ethiopian calendar ( Amharic: የኢትዮጵያ ዘመን አቆጣጠር ye'Ītyōṗṗyā zemen āḳoṭaṭer) also called the Ge'ez calendar,

This rule gives an average year length of 365. 25 days. However, it is 11 minutes longer than a real year. This means that the vernal equinox moves a day earlier in the calendar every 131 years.

Revised Julian calendar

The Revised Julian calendar adds an extra day to February in years divisible by four, except for years divisible by 100 that do not leave a remainder of 200 or 600 when divided by 900. The Revised Julian calendar or less formally New Calendar, is a Calendar scheme originated in 1923 which effectively discontinued the 340 years of divergence between This rule agrees with the rule for the Gregorian calendar until 2799. The first year that dates in the Revised Julian calendar will not agree with those in the Gregorian calendar will be 2800, because it will be a leap year in the Gregorian calendar but not in the Revised Julian calendar.

This rule gives an average year length of 365. 242222… days. This is a very good approximation to the mean tropical year, but because the vernal equinox year is slightly longer, the Revised Julian calendar does not do as good a job as the Gregorian calendar of keeping the vernal equinox on or close to 21 March. A tropical year (also known as a solar year) is the length of time that the Sun takes to return to the same position in the cycle of seasons as seen from Earth Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.

Chinese calendar

The Chinese calendar is lunisolar, so a leap year has an extra month, often called an embolismic month after the Greek word for it. The Chinese calendar is lunisolar, incorporating elements of a Lunar calendar with those of a Solar calendar. A lunisolar calendar is a Calendar in many Cultures whose date indicates both the Moon phase and the time of the solar Year. In the Chinese calendar the leap month is added according to a complicated rule, which ensures that month 11 is always the month that contains the northern winter solstice. Intercalation is the insertion of a leap day week or month into some calendar years to make the calendar follow the seasons or moon phases Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes The intercalary month takes the same number as the preceding month; for example, if it follows the second month (二月) then it is simply called "leap second month" (traditional Chinese: 閏二月; simplified Chinese: 闰二月; pinyin: rùn'èryuè). Pinyin, more formally Hanyu pinyin, is the most common Standard Mandarin Romanization system in use

Hebrew calendar

The Hebrew calendar is also lunisolar with an embolismic month. The Hebrew calendar (הלוח העברי ha'luach ha'ivri) or Jewish calendar is a Lunisolar calendar used by Jews for predominantly religious This extra month is called Adar Alef (first Adar) and is added before Adar, which then becomes Adar Bet (second Adar). Adar ( Hebrew: אֲדָר, Standard Adar Tiberian ʾĂḏār; from Akkadian Adar ( Hebrew: אֲדָר, Standard Adar Tiberian ʾĂḏār; from Akkadian Adar ( Hebrew: אֲדָר, Standard Adar Tiberian ʾĂḏār; from Akkadian According to the Metonic cycle, this is done seven times every nineteen years (specifically, in years 3, 6, 8, 11, 14, 17, and 19). Metonic cycle or Enneadecaeteris in Astronomy and Calendar studies is a particular approximate common multiple of the Tropical year

In addition, the Hebrew calendar has postponement rules that postpone the start of the year by one or two days. These postponement rules reduce the number of different combinations of year length and starting days of the week from 28 to 14, and regulate the location of certain religious holidays in relation to the Sabbath. The names of the days of the week in various world languages can be classified as either numerical or planetary; however in either case the names of one or more days Shabbat or Shabbos ( Hebrew: שַׁבָּת, shabbāt, shabbes, "rest/inactivity" is the Weekly Sabbath In particular, the first day of the Hebrew year can never be Sunday, Wednesday or Friday. This rule is known in Hebrew as "lo adu rosh", i. e. "Rosh [ha-Shanah, first day of the year] is not Sunday, Wednesday or Friday" (as the Hebrew word adu is written by three Hebrew letters signifying Sunday, Wednesday and Friday). The Hebrew alphabet (אָלֶף-בֵּית עִבְרִי alephbet ’ivri) consists of 22 letters used for writing the Hebrew language. Accordingly, the first day of Pesah (Passover) is never Monday, Wednesday or Friday. Passover ( Hebrew, Yiddish: פֶּסַח Pesach, Tiberian: pɛsaħ Israeli: Pesah, Pesakh, Yiddish This rule is known in Hebrew as "lo badu Pesah", which has a double meaning — "Pesah is not a legend", but also "Pesah is not Monday, Wednesday or Friday" (as the Hebrew word badu is written by three Hebrew letters signifying Monday, Wednesday and Friday).

One reason for this rule is that Yom Kippur, the holiest day in the Hebrew calendar, must never be adjacent to the weekly Sabbath (which is Saturday), i. Yom Kippur (יוֹם כִּפּוּר ˈjɔm kiˈpur also known in English as the Day of Atonement, is the most solemn and important of the Jewish holidays Its Shabbat or Shabbos ( Hebrew: שַׁבָּת, shabbāt, shabbes, "rest/inactivity" is the Weekly Sabbath e. it must never fall on Friday or Sunday, in order not to have two adjacent Sabbath days. However, Yom Kippur can be on Saturday.

Years consisting of 12 months have between 353 and 355 days. In a k'sidra ("in order") 354-day year, months have alternating 30 and 29 day lengths. In a chaser ("lacking") year, the month of Kislev is reduced to 29 days. For the Warhammer Fantasy location see Kislev (Warhammer Kislev ( Hebrew: כִּסְלֵו, Standard In a malei ("filled") year, the month of Cheshvan is increased to 30 days. Cheshvan ( Hebrew: חֶשְׁוָן, Standard Ḥešvan Tiberian Ḥešwān) short for 13-month years follow the same pattern, with the addition of the 30-day Adar Alef, giving them between 383 and 385 days.

Islamic calendar

In the Islamic calendar, leap months are not used. The Islamic calendar or Muslim calendar ( Arabic: التقويم الهجري at-taqwīm al-hijrī; Persian: تقویم هجری قمری ‎ The Qur'an says:

Calendars with leap years synchronized with Gregorian

The Indian National Calendar and the Revised Bangla Calendar of Bangladesh organise their leap years so that the leap day is always close to February 29 in the Gregorian calendar. The Indian national calendar (sometimes called Saka calendar) is the official civil calendar in use in India. The Bengali calendar ( বঙ্গাব্দ Bônggabdo or বাংলা সন Bangla Shôn) or Bangla calendar is a traditional solar Calendar Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours The Gregorian calendar is the most widely used Calendar in the world today This makes it easy to convert dates to or from Gregorian.

The Bahá'í calendar is structured such that the leap day always falls within Ayyám-i-Há, a period of four or five days corresponding to Gregorian February 26 – March 1. The Bahá'í calendar, also called the Badí‘ calendar, used by the Bahá'í Faith, is a Solar calendar with regular years of 365 days and Leap Ayyám-i-Há refers to a period of four or five Intercalary days in the Bahá'í calendar, where Bahá'ís celebrate the Festival of Ayyám-i-Há Events 747 BC - Epoch (origin of Ptolemy 's Nabonassar Era 364 - Valentinian I is proclaimed Events 86 BC - Lucius Cornelius Sulla, at the head of a Roman Republic army enters in Athens, removing the Tyrant Because of this, Baha'i dates consistently line up with exactly one Gregorian date.

The Thai solar calendar uses the Buddhist Era (BE), but has been synchronized with the Gregorian since AD 1941. The Thai solar calendar, Suriyakati (สุริยคติ has been the official and prevalent Calendar in Thailand since it was adopted by King The Thai solar calendar, Suriyakati (สุริยคติ has been the official and prevalent Calendar in Thailand since it was adopted by King Year 1941 ( MCMXLI) was a Common year starting on Wednesday (the link will display 1941 calendar of the Gregorian calendar.

Hindu calendar

In the Hindu calendar, which is a lunisolar calendar, the embolismic month is called adhika maas (extra month). The Hindu calendar used in ancient times has undergone many changes in the process of regionalization and today there are several regional Indian Calendars, as A lunisolar calendar is a Calendar in many Cultures whose date indicates both the Moon phase and the time of the solar Year. It is the month in which the sun is in the same sign of the stellar zodiac on two consecutive dark moons. Adhika maas occurs once every two or three years, compensating for the approximately eleven fewer days per year in twelve lunar months than the solar calendar. Thus, Hindu festivals tend to occur within a given span of the Gregorian calendar. For example: the No Moon during Diwali festival tends to occur between October 22 and November 15. Buddhist calendars in several related forms (each a simplified version of the Hindu calendar) are used on mainland Southeast Asia in the countries of Cambodia, Laos, Thailand, Myanmar (formerly Burma) and Sri Lanka. The Buddhist calendar is used on mainland Southeast Asia in the countries of Cambodia, Laos, Thailand, Myanmar (formerly Burma The Thai lunar calendar ( Thai: ปฏิทินจันทรคติ Patitin Chantarakati) (literally Against-the-Sun Moon-Ways) is Thailand

Iranian calendar

The Iranian calendar also has a single intercalated day once in every four years, but every 33 years or so the leap years will be five years apart instead of four years apart. The Iranian calendar or Solar Hejri (تقویم هجری شمسی؛ سالنمای هجری خورشیدی Taqwim Hejri Shamsi Salanmay Hejri Khurshidi) is an astronomical The system used is more accurate and more complicated, and is based on the time of the March equinox as observed from Tehran. Tehran (or Teheran) ( Persian: تهران Tehrān) is the capital and largest City of Iran, and the administrative center of The 33-year period is not completely regular; every so often the 33-year cycle will be broken by a cycle of 29 or 37 years.

Long term leap year rules

The accumulated difference between the Gregorian calendar and the vernal equinoctial year amounts to 1 day in about 8,000 years. This suggests that the calendar needs to be improved by another refinement to the leap year rule: perhaps by avoiding leap days in years evenly divisible by 8,000.

(The most common such proposal is to avoid leap years in years evenly divisible by 4,000. ^[5] This is based on the difference between the Gregorian calendar and the mean tropical year. Others claim, erroneously, that the Gregorian calendar itself already contains a refinement of this kind. ^[6])

A system of 128-year-based leap years has been proposed,^[7] and it can be adopted directly without any modification to current leap year calculations until the year 2048 because no year between now and 2048 is divisible by 128. This rule gives a mean year of 365 + 1/4 − 1/128 = 365. 2421875 days, which is 365 days, 5 hours, 48 minutes and 45 seconds, or one second short of the mean tropical year.

However, there is little point in planning a calendar so far ahead because over a timescale of tens of thousands of years the number of days in a year will change for a number of reasons, most notably:

1. Precession of the equinoxes moves the position of the vernal equinox with respect to perihelion and so changes the length of the vernal equinoctial year. In Astronomy, Precession refers to the movement of the rotational axis of a body such as a planet with respect to Inertial space. In Celestial mechanics, an apsis, plural apsides (ˈæpsɨdɪːz is the point of greatest or least distance of the Elliptical orbit of an object from
2. Tidal acceleration from the sun and moon slows the rotation of the earth, making the day longer. Tidal acceleration is an effect of the Tidal forces between an orbiting Natural satellite ( i

In particular, the second component of change depends on such things as post-glacial rebound and sea level rise due to climate change. Post-glacial rebound (sometimes called continental rebound, isostatic rebound, isostatic adjustment or post-ice-age isostatic recovery) Sea-level rise is an increase in Sea level. Multiple complex factors may influence this change Climate change is any long-term significant change in the “average weather” that a given region experiences We can't predict these changes accurately enough to be able to make a calendar that will be accurate to a day in tens of thousands of years.

Folk traditions

In the English speaking world, it is a tradition that women may propose marriage only on leap years. The word tradition comes from the Latin traditionem acc of traditio which means "a giving up delivering up surrendering" and is used in a number of While it has been argued that the tradition was initiated by Saint Patrick or Brigid of Kildare in 5th century Ireland, it is dubious as the tradition has not been attested before the 19th century. Saint Patrick (Patricius Irish: Naomh Pádraig) was a Roman Britain -born Christian Missionary and is the Patron saint The 5th century is the period from 401 to 500 in accordance with the Julian calendar in Anno Domini / Common Era. Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world The 19th century of the Common Era began on January 1, 1801 and ended on December 31, 1900, according to the Gregorian calendar ^[8] Supposedly, a 1288 law by Queen Margaret of Scotland (then age five and living in Norway), required that fines be levied if a marriage proposal was refused by the man; compensation ranged from a kiss to £1 to a silk gown, in order to soften the blow. Margaret ( Gaelic: Mairead or Maighread) (early 1283&ndashSeptember/October 1290 usually known as the Maid of Norway (Jomfruen av Norge literally ^[9] Because men felt that put them at too great a risk, the tradition was in some places tightened to restricting female proposals to the modern leap day, 29 February, or to the medieval leap day, 24 February. Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the According to Felten: "A play from the turn of the 17th century, 'The Maydes Metamorphosis,' has it that 'this is leape year/women wear breeches. ' A few hundred years later, breeches wouldn't do at all: Women looking to take advantage of their opportunity to pitch woo were expected to wear a scarlet petticoat -- fair warning, if you will. "^[10]

In Denmark, the tradition is that women may propose on leap day 24 February and that refusal must be compensated with 12 pairs of gloves. The Kingdom of Denmark ( ˈd̥ænmɑɡ̊ (archaic ˈd̥anmɑːɡ̊ commonly known as Denmark, is a country in the Scandinavian region of northern Europe Events 303 - Galerius, Roman Emperor, publishes his edict that begins the persecution of Christians in his portion of the

In Greece, it is believed that getting married in a leap year is bad luck for the couple. Greece (Ελλάδα transliterated: Elláda, historically, Ellás,) officially the Hellenic Republic (Ελληνική Δημοκρατία Luck (also called fortunity) is a chance happening, or that which happens beyond a person's control. Thus, mainly in the middle of the past century, couples avoided setting a marriage date in a leap year.

1908 postcard

1908 postcard

Birthdays

A person born on February 29 may be called a "leapling" or a "leaper" ^[11]. Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours In common years they usually celebrate their birthdays on 28 February or 1 March. Birthday is the name given to the date of the anniversary of a person's birth Events 202 BC - coronation ceremony of Liu Bang as Emperor Gaozu of Han takes place initiating four centuries of the Han Dynasty 's rule Events 86 BC - Lucius Cornelius Sulla, at the head of a Roman Republic army enters in Athens, removing the Tyrant

For legal purposes, their legal birthdays depend on how different laws count time intervals. In Taiwan, for example, the legal birthday of a leapling is 28 February in common years, so a Taiwanese leapling born on February 29, 1980 would have legally reached 18 years old on February 28, 1998. Taiwan ( Taiwanese: Tâi-oân/Tāi-oân (historically 大灣/台員/大員/台圓/大圓/台窩灣 is an Island in East Asia. Events 202 BC - coronation ceremony of Liu Bang as Emperor Gaozu of Han takes place initiating four centuries of the Han Dynasty 's rule Leap years Although the modern calendar counts a year as 365 days a complete revolution around the sun takes approximately 365 days and 6 hours Year 1980 ( MCMLXXX) was a Leap year starting on Tuesday (link displays the 1980 Gregorian calendar) Events 202 BC - coronation ceremony of Liu Bang as Emperor Gaozu of Han takes place initiating four centuries of the Han Dynasty 's rule Year 1998 ( MCMXCVIII) was a Common year starting on Thursday (link will display full 1998 Gregorian calendar)

In some situations, March 1 is used as the birthday in a non-leap year since it then is the day just after February 28.

There are many instances in children's literature where a person's claim to be only a quarter of their actual age turns out to be based on counting their leap-year birthdays. A similar device is used in the plot of Gilbert and Sullivan's 1879 comic opera The Pirates of Penzance. Gilbert and Sullivan refers to the Victorian era partnership of Librettist W Comic opera, or light opera, denotes a sung dramatic work of a light or comic nature usually with a happy ending The Pirates of Penzance, or The Slave of Duty is a Comic opera in two acts with music by Arthur Sullivan and Libretto by W

According to DC Comics editor Julius Schwartz, the birth date of Superman is February 29th. DC Comics is an American comic book and related media company Julius "Julie" Schwartz ( June 19, 1915 – February 8, 2004) was a Jewish Comic book and Pulp magazine Superman is a fictional Comic book Superhero widely considered to be one of the most recognized of such characters and an American Cultural icon This was chosen both as a way to keep the character young as well as account for the differences between Earth years and Kryptonian years.

See also

• Leap week calendar
• Leap second
• List of leap years
• Zeller's congruence

References

External links

• Famous persons born on Leap Day
• Leap Day Campaign