It's Thursday, February 29. An unusual day on the calendar that only happens every four years...or almost every four years.
Here are four things to know about this "extra day" during leap years.
1. Multiple of 4 but not 100
Ancient Egypt tried to make their calendar closer to the natural cycle of the seasons. But it was Julius Caesar who introduced leap years with the "reform of the Roman calendar in 708." (the introduction of the Julian calendar in 45 BC), explains the Institute of Mechanics and Calculation of Ephemeries (Institut de mécanique céleste et de calcul des éphémérides - IMCCE), part of the Paris Observatory.
In years with 366 days, the extra day was a double of February 24, i.e. "the sixth day before the beginning of March", hence the French word "bissextile" (leap day).
With the switch to the Gregorian calendar in 1582, "the extra day was added at the end of February, on the 29th day," the IMCCE continued.
Since the Earth does not revolve around the Sun in exactly 365 days and 6 hours, but in 365 days, 5 hours, 48 minutes and a few seconds, not all years that are multiples of four are leap years. Neither are years that are multiples of 100. So 1900 and 2100 do not have a February 29.
2. Aging four times slower
This is what the magnetic French actress Michele Morgan, who died at the age of 96, said. "This privilege of aging four times slower than others is the first of a long series of good fortunes that I have had in my life," said the woman who shares this unusual birthday with Italian composer Rossini, French actor Gerard Darmont, Spanish Prime Minister Pedro Sanchez, American rapper Ja Rule and Canadian comedian Sugar Sammy.
With a one in 1,506 chance of being born on February 29, only a few million people in the world have this original birth date. To be precise, in France since 1968 they have been 27,832, according to INSEE data.
On the border with Mexico, those born on February 29 will still be entitled to a special festival in the small Texas town of Anthony, which has proclaimed itself the leap year capital of the world since 1988.
3. Day of the Bachelor
In Ireland, in 2004 the government paid a €100 bonus to children born on this extra day to mark the tenth anniversary of the International Year of the Family, declared in 1994 by the United Nations.
The Irish still keep in mind an old tradition dating back to the fifth century that makes February 29 "Bachelor's Day" or "Ladies' Privilege": the day when women can ask men to marry them. According to some, the refusal was paid with a gift, and according to others - with a fine. In 2010, it inspired Leap Year, a romantic comedy starring Amy Adams ... named the "worst movie of the year" by Time magazine.
4. Year 2000 Error
As the new millennium approached, all worries focused on a possible major computer crash on January 1st. In the end, February 29, 2000 turned out to be the cause of the scare. According to AFP archives, police computers in Bulgaria were temporarily blocked, as were Japan's meteorological services, the US Coast Guard's message archiving system and Montreal's municipal tax department.
Paris' computerized parking meter system had to be corrected machine by machine because it did not predict February 29, 2000.
Actually, 2000 may not have been a leap year, since years that are multiples of 100 aren't... Unless they're also multiples of 400, like 2000 (or 1600, or 2400). /BGNES
