What is hijri? What is the solar calendar? What is the lunar calendar? What is a Tibetan calendar?

1. Tibetan calendar: It is a popular calendar for Tibetan people. The present Tibetan calendar originated in 1027. The chronology of the Tibetan calendar is basically the same as that of the trunk and branch of the lunar calendar, except that the heavenly stems are replaced by yin and yang and five elements, a is yang wood, b is yin wood, c is yang fire, d is yin fire, e is yang soil, oneself is yin soil, Geng is yang gold, Xin is yin gold, Ren is yang water and Gui is yin water. Replace earthly branches with zodiac signs. It's also a 60-year cycle, but it's not called Jiazi, it's called roundabout. The first round-the-island tour began in A.D. 1027, with the year of Ding Mao in the lunar calendar and the year of the Rabbit in the Tibetan calendar. Tibetan calendar is slightly different from lunar calendar. Instead of taking the new moon as the first day, the full moon is fixed at 15, so it sometimes differs from the lunar calendar by one or two days.

2. Lunar calendar: In astronomy, it mainly refers to the calendar arranged according to the moon phase cycle. The calendar in which the moon orbits the earth for one month, that is, the first month of the lunar calendar is the basis for determining calendar months, and a year is twelve calendar months. In agrometeorology, the lunar calendar is commonly known as lunar calendar, lunar calendar, ancient calendar and old calendar, which refers to the traditional summer calendar in China. Astronomically speaking, the summer calendar is actually a kind of lunar calendar.

3. Gregorian calendar: it is a calendar based on the movement cycle of the earth around the sun. Our country's trunk calendar belongs to this kind of calendar. The Gregorian calendar year is approximately equal to the tropic year, one year 12 months. This "month" has nothing to do with the first lunar month. 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 every month, you can't see the new moon, the new moon, the new moon. At present, the Gregorian calendar, which is commonly used in the world, is a solar calendar, with 365 days in a normal year and 366 days in a leap year, once every four years, once in a hundred years and once again in the 400th year, that is, there are 97 leap years every 400 years. The average length of the Gregorian calendar is only 26 seconds away from the tropic year, and it takes only one day to accumulate 3300 years.

4. hijri: usually expressed by a.h., it is a kind of lunar calendar. It is widely used by Muslims all over the world, as well as in China, mainly in Xinjiang, Gansu, Ningxia, Qinghai and places where Muslims gather all over the country.