The year 1583 is not less than 10 days

That's right, it's really ten days less.

Before 1583, the earth rotated relatively quickly, and the lunar calendar was not yet unified, and it was generally divided into 11 months.

Hearing that from October 5 to October 14, 1583 there was no sound, no one died, and that there were no memorabilia, big or small, were removed, so as not to cause panic.

The date was changed that day (with errors) really, believe it or not.

Summary. The year 1582 was ten days less because of an error in the Julian calendar at the time, which did not exactly match the actual time of the sun.

The fact that 1582 was ten days less was due to an error in the Julian calendar at that time, which did not exactly coincide with the actual travel time of the sun.

To correct this error, Pope Gregory XIII issued a papal decree reforming the Julian calendar to the Gregorian calendar. These include the revision of the rules of leap years to include years so that the average extra days per year (about 11 minutes) are compensated for more accurately the time it takes for the Earth to revolve around the Sun. In order to bring the calendar into line with the actual time of the sun, the papal decree made it possible to skip 10 days on October 15, the day after October 4, 1582, thus reforming the calendar.

This reform was carried out in various European countries, but due to the inconvenient conditions of communication and transportation at that time, the reform time was different in different countries, and it was not until the beginning of the 20th century that the Gregorian calendar was widely adopted in all countries around the world.

The 10 days in October 1582 were due to a fatwa issued by Pope Gregory XIII at the time, a policy also known as the "Gregorian calendar". This time adjustment policy is intended to correct for deviations in previous calendar calculations. Prior to this policy, there had been some deviations in the calculation method of the calendar, resulting in a large difference between the Gregorian calendar and the time when the sun actually runs.

The new calendar was adjusted to the "Gregorian calendar", and October 15, 1582 was used as the boundary point to adjust the decision, and the ten days before this date were removed from the calendar so as to be in line with the accuracy of the calendar calculation. From that day, the "Gregorian calendar" began to take 365 days, 5 hours, 49 minutes and 16 seconds as the length of the year, which is known as the "Gregorian calendar".