How old am I?

The lunar calendar is an ancient algorithm, and the solar calendar is now universal. At 18, 16 years old.

The full name of the lunar calendar is the lunar calendar or the pure lunar calendar. The lunar calendar is based on the cycle of the moon, which is the new moon. Because the ancients called the moon "lunar calendar", it was called "lunar calendar" for short. It is difficult to determine the exact date of the lunar calendar, but judging from the Oracle bones in Oracle Bone Inscriptions, the lunar calendar was quite popular in the Yin Dynasty.

The main feature of the lunar calendar is that the length of the calendar month is determined according to the astronomical phenomena, that is, the phase of the moon, and the average length of the calendar month is roughly the same as that of Wang Shuoyue. 5306 days, etc. The length of a year is only an integer multiple of a calendar month, which has nothing to do with the tropical year. Therefore, the month of the lunar calendar has nothing to do with the four seasons. The date of the lunar calendar indicates a certain moon phase, that is, the first day is the new moon, that is, the new moon; The fifteenth, sixteenth or seventeenth is the full moon, which means hope; The seventh and eighth days are the first quarter moon; Twenty-two and twenty-three are the last quarter moons, and it is very convenient for the ancients to judge the date by the phase of the moon. The change of the moon phase is the easiest astronomical phenomenon to see, so most of the calendars in various countries have the lunar calendar first and then the solar calendar. However, because the lunar calendar has nothing to do with the tropical year, it is not harmonious with agricultural production and people's daily life, and it was gradually eliminated. Today, except for a few Islamic countries that still use a lunar calendar called "hijri" for religious reasons, all other countries have given up.

In addition,. 19 12 after China adopted the Gregorian calendar to arrange the months, people called it the Gregorian calendar, while the traditional summer calendar coexisting with the people was popularly called the lunar calendar.

1. The origin of the Gregorian calendar is the Gregorian calendar as well. It is international. Since the first year of the Republic of China, China has adopted the solar calendar, which is symmetrical with the old calendar of China. The solar calendar is also called the "new calendar". The solar calendar takes one year for the earth to make a circle around the sun. ***365 days, 5 hours, 48 minutes and 46 minutes. An average year is only an integer of 365 days, not a mantissa. The solar calendar is divided into 12 months, 3 1 day for the big month, 30 days for the small month, and only 28 days in February. It is also stipulated that before July, a single month is a big month and a double month is a small month; After August, two months are big months and one month is small months. The remaining 5 hours, 48 minutes and 46 seconds each year, there is only one day in about four years, and this day is added in February of the fourth year. This year is called leap year, so February in leap year has 29 days.

2. Determination of leap years in the solar calendar Generally speaking, if the year of the solar calendar is divided by 4, leap years can be divided, such as 1984, 1988. However, because the exact number of days in a solar calendar year should be 365 days, 5 hours, 48 minutes and 46 seconds, 5 hours, 48 minutes and 46 seconds more than the normal year and 23 hours 15 minutes and 4 seconds more than the four-year calendar. If one day is added every four years, it will add 44 points and 56 points, and almost three days in 400 years, then three days will be deducted every 400 years. Therefore, a supplementary provision is made: every solar year is a full hundred years, such as 1800,1900,2000, etc. , divisible by 400, so it is not a leap year. But 2000 is a leap year, because its February has 29 days.

3, the origin of the lunar calendar The lunar calendar takes the full moon of the moon as a month, ***29 days and a half. For the convenience of calculation, the big moon is customized for 30 days and the small moon is customized for 29 days. During the period of 65438+mid-February of a year, generally, large and small months are arranged alternately. There are about 365 days in the lunar calendar year, and there is no difference between a normal year and a leap year. The lunar calendar does not consider the movement of the earth around the sun, so the changes of the four seasons in the lunar calendar have no fixed time and cannot reflect the seasons, which is a great shortcoming. In order to overcome this shortcoming, people later decided on a new calendar, which is the so-called yin-yang desk calendar. The summer calendar (also called lunar calendar or lunar calendar) still in use in China is this kind of lunar calendar. Like the lunar calendar, it customizes a month according to the time when the moon wanes, that is, 30 days in the big month and 29 days in the small month, but it also adopts the method of adding leap months to make the average number of days in a year close to that in the solar calendar to adjust the four seasons. The lunar calendar has a leap month every two or three years.

4, the determination of the lunar calendar leap month As for which month of the lunar calendar, this involves the solar terms. There are 24 solar terms in a year, which is just a traditional saying. In detail, it should be said that there are twelve solar terms and twelve neutral terms in a year. Which of the twelve qi belongs to which month is regular: rain is the qi of the first month; The vernal equinox is in mid-February; Grain Rain is the spirit of March; Xiaoman is the spirit of April; The solstice in summer is mid-air in May; The summer heat is in mid-June; Summer heat is the qi of July; The autumnal equinox is in mid-August; The first frost is the breath of September; Light snow is the neutral atmosphere in October; The winter solstice is 1 1 mid-month; It's freezing in mid-air in December. As for which month the ten solar terms are in, that is not necessarily the case. A month in the lunar calendar averages a little more than 29 and a half days, but the average interval from one breath to the next is less than 30 and a half days. In this way, the monthly air in the lunar month will be delayed by 1 day. At a certain time, qi is not in the middle of the month but moved to the end of the month. If next month is a miscarriage, there will probably be no gas in this month, because the gas will be moved to the beginning of the third month. The middle month is not neutral, even if last month was a leap month. Take 1998 as an example: June 2 1 day in the solar calendar is May 27th of the lunar calendar, which is the summer solstice (mid-May); But July 23rd in the solar calendar is the first day of June in the lunar calendar, and this day is the summer heat (the qi of June). From June 24th to July 22nd of the Gregorian calendar (one month after the end of May of the lunar calendar), there is only one solar term, and this month is leap May. Therefore, leap month is determined by people according to certain laws, which is not mysterious.