Talking about sun advertising

In fact, when the sun was first defined, not all months in a year were 12 months.

This moon has nothing to do with the moon. The month and date of the solar calendar are very consistent with the position of the sun on the ecliptic. According to the date of the solar calendar, we can clearly see the changes of cold and warm seasons in a year. But the date of each month has nothing to do with the change of the moon phase.

At present, the popular Gregorian calendar in the world is the most familiar Gregorian calendar. This calendar is saturated with the civilization created by human beings for thousands of years. It was learned by the ancient Romans from the Egyptians and spread all over the world with the expansion of the Roman Empire and the rise of Christianity.

Let's talk about the ancient Roman calendar first.

The ancient Roman calendar lasted as early as 65,438+00 months, some 30 days, some 29 days (much like the lunar calendar), and there were more than 70 days off at the end of the year. During the period of romulo, the first king of Rome, there was a name and an order every month. There are 10 months throughout the year, some months have 30 days, some months have 3 1 day, ***304 days, and the other 60 days are year-end rest days.

The second king, Nouma, made a reform according to the Greek calendar, adding 1 1 month and 1 February, and adjusting the number of days in each month to1,3, 5 and 8, 3 1, 2, 4, 6, 7, 9,/. In order to correct the deviation of date and season year by year, two supplementary months are added every four years. The first supplementary month has 22 days, which will be increased in the second year and another 23 days in the fourth year. The added days are between1February 24th and 25th.

When Julius Caesar served as consul for the third time, he appointed a group of astronomers headed by Egyptian astronomer Sotchini to make a new calendar, that is, julian calendar.

The main content of julian calendar is to set up a leap year every three years, with 365 days in a normal year and 366 days in a leap year, with an average length of 365.25 days. Take the original 1 1 month 1 as the beginning of the year, so that the Roman consul will take office on New Year's Day. Julian calendar is divided into 12 months every year, 1, 3, 5, 7, 9,1/month is a big month, and 3 1 day is a month. The 4th, 6th, 8th, 10 and 12 months are the abortion periods, with 30 days of abortion every month. The second month (original1February) has 29 days in a normal year and 30 days in a leap year. Although the order of months is different from that before the calendar change, it still retains its original characteristics and is the shortest month in a year.

Gregorian calendar of ancient Egypt-1February

The first year was set at 360 days, and later it was changed to 365 days. This is the first solar calendar in the world. Later, according to the situation of Nile flooding and agricultural production, they divided the year into three seasons, called flood season, winter and summer. Four months per quarter, 30 days per month, 10 days per week, five days per week. The whole year 12 months, plus five days at the end of the year, is the year-end sacrifice day. This 365-day calendar year was determined by observing Sirius, which is called Sirius Year.

Mayan solar calendar-1August

The solar calendar Haab' is a Venus calendar based on astronomical calculation, so it is very important for the Mayan agricultural daily life. There are 18 months in a year, 20 days in each month, and 5 taboo days (unlucky days, which Maya thought would open the door between the world and hell), so the year is 365 days. After long-term observation and careful calculation, the Maya, who are good at astrological observation, revised the length of a year to 365.4438+029 days, which is less than one tenth of the absolute length of 365.438+098 days measured scientifically today.