We are talking about the particular year that occurs once every four and that has 366 days thanks to February 29.
It takes the Earth approximately 365.242189 days, or 365 days, 5 hours, 48 minutes and 45 seconds, to go around the Sun. It is what we call the tropical year and is measured from the March equinox.
However, the Gregorian calendar has only 365 days in a year, so if we did not add a business day to February 29 almost every four years (then having 366 days), we would lose practically six hours of our calendar annually. It seems like a small thing, but after 100 years, our calendar would have lost 24 days! Thus, every four years in the Gregorian calendar, we add an additional day to the calendar to synchronize it with the solar year.
As a curiosity, in the Julian calendar, there is still a discrepancy of 11 minutes and 14 seconds each year.
It occurs in each year that is divisible by four and only in years of a century that are divided by 400. For example, the years 800, 1200 and 2000 were leap, but 1700 and 1900 were not because they are not divisible by 400 , a even though they are divisible by four. Also, 2400 is a leap year, while 2100, 2200, 2300, and 2500 are not.
The history of the leap day / year
The practice of including an additional day begins with the creation of the Julian calendar and a decree of the Roman Emperor Julius Caesar. The expression ‘leap year’ derives – therefore – from the Latin bis sextus dies ante calendas martii , which corresponded to an extra day interspersed between February 23 and 24.
(The Julian calendar created the directive to add an additional day every four years but did not follow the rule of the century divisible by 400). And it is that the Julian had that only rule: any year divisible by four would be a leap year.
This formula produced too many leap years, but it was not corrected until the introduction of the Gregorian calendar more than 1500 years later.
Thus, the 11-minute discrepancy in the Julian calendar means that by 1582 AD up to 10 days would have been lost in the calendar.
To solve this, Pope Gregory XIII creates the Gregorian calendar , makes 10 days of the month of October 1582 jump and establishes February 29 as the official day to be included during a leap year, coining the term leap year and creating the norms to annex the same, in order to terminate the adjustment for time lag.
When was the last leap year? In 2020 (and previously in 2016).
Here are the next 10 leap years:
2024, 2028, 2032, 2036, 2040, 2044, 2052, 2056.
Why are frogs often associated with leap years?
Frogs symbolize leap years because in English leap year is “leap”, which also means to jump, hence the sympathetic association with these amphibians. Hence, those born on February 29 are nicknamed ‘jumpers’. It is not easy at all, since the chances of being born on a leap day are 1 in 1500.
Events in history that occurred in leap years:
The Titanic sank in 1912
Benjamin Franklin proved that lightning was an electrical phenomenon in 1752
Gold was discovered in California (USA) in 1848
