Traditional Culture Encyclopedia - The 24 Solar Terms - Tomb-Sweeping Day, why is the time not fixed?
Tomb-Sweeping Day, why is the time not fixed?
When Tomb-Sweeping Day is angry, the earth revolves around the sun 15 degrees. However, because the time of the earth's revolution is not necessarily 365 days, there may be a phenomenon that the date is not fixed in the division of solar terms.
Under normal circumstances, the Qingming Festival is about 15 days after the vernal equinox every year, and the specific date changes no more than three days.
Because the length of a year is determined by the movement of the sun, and the 24 solar terms are also determined by the position of the sun, basically the date of each solar term will not change much every year.
However, the time that the earth orbits the sun is called the "tropic year". The actual length of a tropical year is 365.2422 days, and the Gregorian calendar year is 365 days, so there will be 0.2422 days more each year, and the specific time of solar terms will be "delayed" by 0.2422 days each year.
In this way, the cumulative time after 4 years is 0.9688 days, almost one day. In order to correct mistakes, there is a "leap year" system in the Gregorian calendar, with one more day on February 29th every four years.
If the solar term is delayed from midnight to the next day, or advanced to the previous day due to leap year, the date of the solar term will change, but the date difference will only be within three days.
According to astronomical experts, in recent decades, the date of Qingming has been changing from April 4 to 6.
References:
Why is the date in Tomb-Sweeping Day not fixed? How to calculate the date in Tomb-Sweeping Day? _ Calendar.
- Previous article:Suzuki uu 125 scooter accelerates as soon as the fan rings.
- Next article:The sunniest month of the year.
- Related articles
- Making technology of paper-cut stereoscopic painting
- A selection of baby nicknames born in May 2022
- What's the difference between beginning of autumn, early summer, white dew, autumnal equinox, cold dew and early frost?
- The purpose of regular soot blowing on the heating surface is
- What festival?
- Will fish land on a spring night?
- Why don't you suggest washing the throttle?
- The cold weather makes me itch all over as soon as I go out. What is the reason?
- In the rain, one holds an umbrella for you and the other gets wet for you. Which one do you choose?
- What animals are there in summer solar terms? Changes of animals in summer solar terms.