Today is Leap Day.
As most people understand Leap Day, they fall on Feb. 29 every four years on the Gregorian calendar, which is the standard calendar for most of the world. The entire year in which a Leap Day falls is known as a Leap Year.
Common knowledge says that the reason for Leap Day is to compensate for the fact that a period of 365 days is shorter than a solar day by six hours. Hence
the extra day every four years (6 x 4 = 24 hours). Since seasons and astronomical events don’t happen in a whole number of days, the extra day is inserted to drift the calendar back to an even number,
However, it does get a little bit more complicated. There are in fact, calendar experts (known as dayologists). Apparently, it likely is not a lucrative business when their services are needed only every four years, so there are not many of them.
On the Gregorian calendar, the “drift” is not actually an even six hours, but is 5 hours, 49 minutes and 12 seconds. To further account for this, every fourth year fully divisible by 100 is not a leap year unless it is also divisible by 400. (For example, 1700, 1800 and 1900 were not Leap Years, but 2000 was.) This makes most people in today’s generation in a rare position of not having that skipped year, since it will be 2400 before it occurs again.
The Gregorian calendar was designed to keep the vernal (spring) equinox on or close to March 21 so that Easter always falls on the Sunday after the 14th day of a the full moon. The vernal equinox, though always changing, is about 365.242374 days long. This causes a marginal difference of about .000125 days difference between a Gregorian calendar average year and an actual year. This actually means that in 8,000 years, we will lose a day. However, when that time rolls around, an extra non-Leap Year is planned depending on the ever-changing vernal equinox.
While the Gregorian calendar is what is most commonly used by most modern countries, several other calendars are currently in use.
The Julian calendar adds the extra Feb. 29 days without exception. The Coptic and Ethiopian calendars add an extra day at the end of the year every four years. This means with those calendars spring moves a day earlier every four years.
The Chinese calendar is lunisolar, so an extra month is added when needed. On the Hebrew calendar is on a cycle where a “Leap” is added seven times every 19 years in years 3, 6, 8, 11, 14, 17 and 19 of the cycle. Other calendars in use today that make changes include the Islamic, Indian National, the Revised Bangla, Hindu and Iranian calendars.
Surprisingly, there have not been many traditions to develop in the United States in celebration of Leap Day or Leap Year. However, many traditions have developed world-wide.
In England, it is common tradition that women can propose marriage only in leap years.
In 1288, Queen Margaret of Scotland (only five years old at the time) required that fines be levied if a marriage proposal was refused by a man in a leap year. Compensation ranged from a kiss to 1 pound to a silk gown.
In Denmark, the tradition is women may propose on Bissextile Leap Day, Feb. 24, and refusal must be compensated with 12 pairs of gloves. In Finland, refusal of a woman’s Leap Day marriage proposal must be met with fabrics to make a skirt.
In Greece, it is considered extremely unlucky to marry on a Leap Year and only one in five couple on average actually get married.
Sadie Hawkins Day, which was actually created in the Li’l Abner comic strips in 1937, is now traditionally considered to be on Feb. 29. The tale of the comic strip was all eligible bachelors were given a fair head start in a race to get away from Sadie, the homeliest girl in Dogpatch. The first man caught in the race, held between Nov. 19 and Nov. 30, suffered matrimony as a consequence. The closeness in other traditions with women proposing marriage has evolved to many declaring Feb. 29 Sadie Hawkins Day.
In many examples of literature and in real life situations, people have declared to be only a quarter of their true age. In the Pirates of Penzance, Frederic the pirate apprentice glumly learns he is bound to serve the pirates until his 21st birthday rather than his 21st year.
For legal purposes, it is implied in China that a person born on Leap Year turns a year older on Feb. 28, for example, but laws in Hong Kong declare it to be March 1.