List of leap years and days

A year with one more day than usual is called a leap year. The extra day appears in February. This phenomenon almost always occurs once every four years, and it is necessary for calendar years to coincide with astronomical years. 

 

The concept of a leap year comes from the Latin word bis sextus, which means "second sixth". The fact is that before the reform of Gaius Julius Caesar in 45 BC, an extra month was periodically added to the year to adjust the calendar. In some cultures, for example, this is still done in Israel. By the 40s BC, the Roman calendar, which was used in everyday life, was ahead of the solar calendar by three months. Then, Julius Caesar introduced a new calendar. Now, every four years in February, an extra day appears. In the calendar, this was the second, sixth day before the March calends. That is, February 29 did not exist. The Romans did not immediately understand the principle of the Julian calendar. So, the priests responsible for its functioning began introducing an extra day every three, not every four years. The Julian calendar was established only in 8 AD.

 

Over time, the Latin word bis sextus changed, and the year acquired its current name. A regular calendar year consists of 365 days. However, this value is approximate - the Earth makes a full revolution around the our star in 365 days, 5 hours, and 49 minutes. This is the so-called 'tropical year', which is the basis for the concept of leap years.

 

At one time, leap years were introduced actually for convenience. In reality, a year lasts 365 days and almost 6 hours. During this time, the Earth makes one full revolution around the sun. Therefore, whether 365 or 366 days, these are still inaccurate values. When there was a 365-day year, people noticed that the seasons gradually changed according to the calendar from year to year. They realized it was inaccurate, and one of the four years became longer by one day, which compensated a little. 

 

As a result, the seasons shift, and the leap year shifts by almost a day. This means that the vernal equinox, for example, can occur on different dates in different years. For instance, the vernal equinox last year was on March 21 at 4:00 a.m., and this year, it is expected to be on March 20 at 10:00. This shifting of seasons is a practical implication of the concept of leap years.

 

A large number of superstitions and signs are associated with a leap year. This is associated with cataclysms, deterioration in the quality of life, and many other troubles. For example, the coronavirus pandemic began last leap year.

 

A leap year has long been associated with bad luck in many countries. In France, such years were called barren, and in Italy, people were afraid to have children - it was believed that a leap year could lead to the death of a mother or child. Unfortunately, people born on February 29 have a birthday only once every four years. Although many people in the world are born on this day, they usually celebrate their birthday on February 28 or March 1. According to maternity hospitals, parents often try to register their children born on February 29 for one of these two dates so that the child does not get upset about the lost holiday.