Essays on the Twenty-four Solar Terms (14) Little Summer: The prelude of the Sky Stage has begun.

There is a cloud in ancient times: the sky is like a vault, and the cage covers four fields. Indeed, looking up at the sky, the sky is a big semicircle. And if it is combined with the other half at the foot, isn't it a big ball?

So there was the concept of celestial sphere. On the celestial sphere, the sun, the moon and the stars rise and fall on it, each with its own trajectory. And if you draw latitude and longitude lines again, the positioning of any celestial body will be clear.

For example, the division of twenty-four solar terms is obtained by dividing the sun's trajectory 360 on the celestial sphere by 24, so we see that every 15 degrees turns into a solar term.

Taking spring as 0 degrees, we have experienced Qingming, Grain Rain, Long Summer, Xiaoman, Mangzhong and Summer Solstice. It's a slight summer heat. Let's see, it's 105 degrees, right?

The summer heat is the first solar term from summer to the future. The sun has returned to the south, but its altitude angle is still so big, so the heat is still accumulating and the summer heat is gradually coming over.

The summer heat has arrived and started on the big stage in the sky. Wind, clouds, thunder, electricity and rain appeared alternately, and a magnificent drama was staged.