What do you mean by intersection?

The intersection point means that the sun (based on the earth) passes through the longitude of longitude 0, 15, 30, 45, 60, 75, 90, 105, 120, 135,/kloc-.

The time when the sun runs along the longitude of the Yellow River from zero 15 degrees is called "a solar term". It runs 360 degrees every year, and * * * experiences 24 solar terms, twice a month. Among them, the first festival of each month is "Festival", namely: beginning of spring, Jingzhe, Qingming, Changxia, Mangzhong, Xiaoshu, beginning of autumn, Bailu, Hanlu, beginning of winter, Heavy Snow, Xiaohan, etc. 12 festivals; The second month is qi, that is, rain, vernal equinox, Grain Rain, Xiaoman, summer, great heat, early relaxation, autumn equinox, early frost, light snow, winter and severe cold. 12. "Festival" and "Qi" appear alternately, each lasting about 15 days. Now people have called "festival" and "qi" solar terms.