Look at the vernal equinox in the yellow calendar

The spring equinox is about March 2 1 day, the summer solstice is about June 22, the autumn equinox is about September 23, and the winter solstice is about June 22. The exact time and minutes are not fixed, so you need to check the old almanac.

The vernal equinox on March 20th or March 2nd1day in the solar calendar is when the sun is at 0. At the vernal equinox, the direct point of the sun is on the equator, and the northern and southern hemispheres are equally divided day and night. After that, the direct point of the sun continues to move northward, so the vernal equinox is also called "rising equinox".

The summer solstice is usually on June 2 1-22 of the Gregorian calendar, that is, when the sun runs to 90 degrees of the yellow meridian. On the day of summer solstice, the position where the sun directly hits the ground reaches the northernmost point of the year, almost directly on the tropic of cancer. At this time, the daylight hours in all parts of the northern hemisphere reach the longest in the whole year.

The autumnal equinox usually falls from September 22 to 24 of the Gregorian calendar every year. On the day of the autumnal equinox, the sun reaches the longitude 180 (autumnal equinox), which almost directly reaches the equator of the earth, and is as long as day and night all over the world.

On the winter solstice, the solar meridian reaches 270, and this festival is held on the Gregorian calendar 65438+February 2 1-23 every year. The winter solstice marks the lowest sun height and the shortest day in the northern hemisphere.