What do you mean by vernal equinox?

In fact, the vernal equinox, autumnal equinox, summer solstice and winter solstice are collectively called vernal equinox. The dates of these four points in the northern and southern hemispheres are inconsistent, but we can understand it like this:

If in the northern hemisphere,

3/ 19, 20, 2 1, vernal equinox-when the sun shines directly at the equator and begins to move toward the tropic of cancer, it is March 2 1 every year, which is the vernal equinox of the China lunar calendar;

6/22, Summer Solstice —— When the sun directly hits the Tropic of Cancer and begins to return to the equator, it is June 22nd every year, which is the summer solstice of the China lunar calendar, and the northern hemisphere enters midsummer on this day;

9/22 or 23, autumnal equinox —— When the sun returns from the Tropic of Cancer, points to the equator and moves towards the Tropic of Capricorn, it is the autumnal equinox of the China lunar calendar on September 22nd or 23rd every year. In the northern hemisphere, due to the short exposure time of the sun (it gets dark earlier), the exposure angle is getting bigger and bigger, and it gradually turns cold;

12/22, the winter solstice-when the sun reaches its southernmost direct point-Tropic of Capricorn, is 12/22 every year, which is the winter solstice of the China lunar calendar. This day is the shortest sunshine day in the northern hemisphere, and the weather is getting cold.

In the southern hemisphere, the situation is just the opposite!