Double Ninth Festival in September

Solar terms can be understood as two meanings: one is one of the twenty-four qi. Since the slight cold, every 30-degree increase in the solar meridian is another solar term. There are slight cold, beginning of spring, Jingzhe, Qingming, Changxia, Mangzhong, Xiaoshu, beginning of autumn, Bailu, Hanlu, beginning of winter and Daxue. It's called twelve solar terms. Second, the floorboard of the twenty-four qi. Solar terms are generally calculated according to the solar calendar.

The earth revolves around the sun at 5: 48: 46 every 365 days and rotates once every 24 hours. Because the orbital plane of the earth's rotation is not the same as the equatorial plane, but maintains a certain inclination angle, the position of the direct sunlight on the earth is different all the year round. In the northern hemisphere, when the sun is directly at 23.5 degrees north latitude, it is called summer solstice in astronomy; When the sun shines directly at 23.5 degrees south latitude, it is called the winter solstice; The solstice in summer and the solstice in winter mean that it is halfway between summer and winter. Twice a year, when the sun shines directly on the equator, it is the vernal equinox and the autumnal equinox, which are in the middle of spring and autumn. The day is as long as the night. The solar terms reflecting the changes of the four seasons are: beginning of spring, Spring Equinox, Long Summer, Summer Solstice, beginning of autumn, Autumn Equinox, beginning of winter and Winter Solstice. Among them, beginning of spring, Changsha, beginning of autumn and beginning of winter are called "Li Si", which means the beginning of the four seasons. There are five solar terms reflecting temperature changes: slight summer heat, great summer heat, summer heat, slight cold and severe cold. There are seven solar terms reflecting weather phenomena: rain, Grain Rain, white dew, cold dew, first frost, light snow and heavy snow. There are four solar terms reflecting phenological phenomena: Jing Zhe, Qing Ming, Xiaoman and Mang Zi.

spring

The sun in beginning of spring is located at 365, 438+05 degrees of the Huangjing, and the solar term is from February 2 to 5.

The rainy day is located at 330 degrees longitude of the Yellow River and will be on February 18-20.

The stung sun is located at 345 degrees of the yellow meridian, and it will pass through on March 5-7.

At the vernal equinox, the sun is located at 0 degrees of the yellow meridian and crosses on March 20-22.

The Qingming sun is located at longitude 15 degrees, and the festival will be held on April 4-6.

The sun in the Grain Rain is located at 30 degrees longitude of the Yellow River and intersects in April 19-2 1.

summer

The sun in the long summer is located at 45 degrees of the yellow meridian, and there will be solar terms from May 5 to 7.

Xiaoman sun is located at 60 degrees of the yellow meridian, and the solar term will be celebrated on May 20-22.

The awn seed sun is located at 75 degrees of the yellow meridian and intersects on June 5-7.

The summer solstice sun is located at 90 degrees of the yellow meridian, which intersects with June 2 1-22.

The light summer sun is located at 105 degrees, July 6-8.

In summer, the sun is located at 120 degrees, and the solar term passes on July 22-24.

autumn

The sun in beginning of autumn is located at longitude 135 degrees, and the solar term will pass on August 7-9.

In summer, the sun is located at 150 degrees, and the solar term passes on August 22-24.

The Millennium sun is located at longitude 165 degrees, and will pass the solar term on September 7-9.

The autumnal equinox sun is located at 180 degrees, and will pass the solar term on September 22-24.

The cold dew sun is located at the node of longitude 195 degrees and 65438+1October 8-9.

The sun in the first frost is located at longitude 2 10, and the node is 65438+1October 23-24.

winter

The sun in early winter is located at 225 degrees of the yellow meridian and intersects with165438+1October 7-8.

Xiaoxue Sun is located at the intersection of165438+1October 22 -23 at longitude 240 degrees.

The snowy day is located at 255 degrees of the yellow meridian, and the node is 65438+February 6-8.

In winter, the solstice sun is located at 270 degrees of the yellow meridian and intersects with 65438+February 2 1-23.

The slight cold sun is located at 285 degrees of the yellow meridian, and the node is 65438+1October 5-7.

The severe cold day is located at 300 degrees of the Yellow Meridian and intersects with 65438+1October 20th -2 1.