The days become longer and shorter, the sun moves farther and closer, nights follow days… and plants and animals perceive the planet’s annual rhythm better than humans. Reasonable beings tried to express these changes with calculations, numbers and letters. Every culture has its own system, related to religion, nature, politics or reason; And don’t be surprised if the flat earthers or anti-vaccines question each other by the end of the year.

Next year 2024 will be a leap year, how often does that happen?

The universal system by which we count years, months and days is the Julian-Gregorian calendar. It was created by Julius Caesar 46 years before Christ, and modified by Pope Gregory XIII in 1582.

Before 46 BC, the Roman year had 304 days divided into ten months (six of 30 days and four of 31), and every two or three years a month was added to re-square the seasons. When Julius Caesar fixed a year of 365 days, the Egyptians added the same amount for 15,000 years: the Nile rose every year exactly and marked their dates almost as precisely as the moon and the sun.

For the Egyptian sages who worked for Julius Caesar, the year had 365 days and 6 hours, which is why they added it every four.

Julius Caesar hired a wise Egyptian who knew a lot about matching dates and, above all, fitting them into the festivities that marked the year. 44 BC was the first leap year, because they also knew that every four years they had to add a day if they didn’t want winter to turn into autumn. The day added was the second February 24, six days before March: ante diem sextum kalendas martias, and since there were two February 24s in those years, the second was called bis sextus.

Then they fiddled with the months and days each has, but never changed the number of days in the year or the leap year every four. Octavius ​​Augustus gave his name to the sixth, who was no longer the sixth but the eighth, imitating the decision of the Senate to name the fifth, who was no longer the fifth but the seventh, after Julius Caesar.

How often does a leap year repeat itself?

For the Egyptian sages who worked for Julius Caesar, the year had 365 days and 6 hours, which is why they added it every four. But with the centuries, the years became erratic again. Well calculated, the year has 365 days, 5 hours, 48 ​​minutes and 45.16 seconds. This agreement came into force under Gregory’s pontificate

But the Gregorian reform didn’t just eat up those days from 1582. They did their homework well – with the clocks of the time! – to combine the times of the Earth’s rotation with the transit around the Sun as much as possible. Thus they established as leap years (of 366 days) years divisible by 4, but excluding multiples of 100, from which those also divisible by 400 were also excluded; That’s why 2000 was not a leap year, and 2400 will be, but we don’t plan to be there to certify it. Divisible by 4 is 2024, so it will have one more day and also the Olympics, another event that takes place on leap days, as long as there is no pandemic or world war. (OR)