What's the date?
1. The first day of the month is the new moon (new moon: the sun and the moon are at the same longitude on the celestial sphere. Astronomically speaking, the longitude difference between the sun and the moon at this time is equal to zero. In fact, at the new moon, the sun, the moon and the earth are all close to a straight line. At this time, the moon in the middle, the half that is not illuminated by sunlight, is facing the earth, and the moon can't be seen on the earth. The orbit of the moon (ecliptic) and the orbit of the sun (ecliptic) are not on the same plane. There is an included angle of 59 between the ecliptic plane and the ecliptic plane. On the first day, if both the sun and the moon move near the intersection of the ecliptic and the ecliptic, and the sun and the intersection make a certain angle (eclipse limit), an eclipse can occur. The solar eclipse must occur on the first day of the lunar calendar, and there may not be an solar eclipse on the first day. For example, in 2009, there were eclipses on the first day of the first month, the first day of June and the first day of December in the ugly year of the lunar calendar.
2. With the winter solstice (winter solstice), the sun reaches the tropic of Capricorn, with the shortest day and the longest day in a year being the winter solstice. According to the regulations, the year from the winter solstice to the following winter solstice is the year of the tropic of cancer. A year is divided into twenty-four "qi", which is called twenty-four solar terms. ) Starting from 270 degrees of the ecliptic, every time the sun moves 15 degrees on the ecliptic, it is designated as a solar term or neutral gas. Severe cold, heavy rain, vernal equinox, etc. Are called neutral gases; The other 12 species, such as: slight cold, beginning of spring, fright, etc. , are called solar terms.
3. Take the month from the winter solstice as November of the lunar calendar, and set up a child as the beginning of the calendar.
4. If the interval between two "winter solstices" is 1 1 month, there is no need to set a leap, and then arrange December, January, February, March of the lunar calendar ... October of the following year. The first month is the first year of civil use, and it is the first time to build Yin.
5. If the interval between two "winter solstices" is 12 months, a leap is needed. The leap month begins on the "winter solstice". When there is no "neutral spirit" in the first month, this month is a leap month, and its name is to add the word "leap" before the previous month.
6. The meridian of the lunar calendar is east longitude 120, which is the time zone of Dongba District where Beijing is located (Beijing time).
For example:
The interval between winter solstice in 2008 and winter solstice in 2009 is 12 months, so it is necessary to set the first month without "neutral gas", that is, the eighth month starting from1month of the lunar calendar in 2008. The calendar month is:
Lunar year 2008 1 1 month (winter solstice);
Lunar calendar 20081February (cold air);
The first month of the lunar calendar in 2009 (rain in the air);
Lunar February 2009 (vernal equinox);
Lunar March 2009 (Grain Rain Zhongqi);
Lunar April 2009 (small full of gas);
May of the 2009 lunar calendar (summer solstice);
Lunar New Year leap in May 2009 (lifeless);
June of the 2009 lunar calendar (midsummer);
July (summer) of the lunar calendar in 2009;
August (autumnal equinox) of the 2009 lunar calendar;
September of the lunar calendar in 2009 (the first frost is in the air);
October of the lunar calendar in 2009 (light snow in the air);
Another example is:
The interval from the winter solstice in 2032 to the winter solstice in 2033 is 1 1 month, and there is no need to set a leap, although there is no "neutral gas" for one month. The calendar month is:
Lunar year 2032 1 1 month (winter solstice);
Lunar calendar 20321February (cold in the air);
The first month of the lunar calendar in 2033 (rain in the air);
Lunar February 2033 (vernal equinox);
Lunar March 2033 (Grain Rain Zhongqi);
Lunar April 2033 (small full of gas);
May of the lunar calendar in 2033 (summer solstice);
Lunar June 2033 (midsummer);
Lunar July 2033 (midsummer);
Lunar August 2033 (lifeless);
Lunar September 2033 (autumnal equinox);
Lunar calendar 2033 10 month (the first frost is in the air);
Another example is:
The interval from the winter solstice in 2033 to the winter solstice in 2034 is 12 months, so it is necessary to set a leap. Although there was no "neutral gas" for two months, the first month without "neutral gas" was set. The calendar month is:
Lunar calendar 2033 1 1 month (light snow in the air, winter solstice in the air);
Lunar leap year 2033 1 1 month (lifeless);
December of the lunar calendar in 2033 (cold in the air, rainy in the air);
The first month of the lunar calendar in 2034 (lifeless);
Lunar February 2034 (vernal equinox);
Lunar March 2034 (Grain Rain Zhongqi);
Lunar April 2034 (small full of gas);
May of the lunar calendar in 2034 (summer solstice);
Lunar June 2034 (midsummer);
Lunar July 2034 (in the summer);
Lunar August 2034 (autumnal equinox);
Lunar September 2034 (the first frost is full of gas);
Lunar calendar 2034 10 month (light snow in the air);
As for the perihelion of the twelfth lunar month and the first lunar month, the revolution speed is faster, the interval between winter solstice, severe cold and rain is short, and the probability of leap month is rare. The latest leap month is 2262, and the latest leap month is 3358.
Leap on the first day of the first month in 2262 (February 20th in Gregorian calendar).
Leap month 29, 2262 (March 20, 2262 Gregorian calendar)
The first day of the leap twelfth lunar month in 3358 (Gregorian calendar 33591October 65438+2 1 day)
On the 29th New Year's Eve of the twelfth lunar month in 3358 (February 3359 18).