How is beginning of spring determined every year?

1, "beginning of spring" is calculated according to the ecliptic. When bucket handle points to the overcast, it is the beginning of spring solar term, that is, when the sun reaches longitude 3 15.

2. The earth's orbit around the sun was named "ecliptic" by the ancients, also known as "solar path". The ecliptic is divided into 24 equal parts, separated by 15, forming 24 solar terms. 24 solar terms is actually 24 solar terms, with 2 solar terms per month. Each solar term has three cycles, and each cycle is five days.

3. beginning of spring is a time point or period. China tradition divides beginning of spring's Tenth Five-Year Plan into three periods: "The east wind thaws, the insects start to vibrate, and the fish get cold", which means that the east wind warms and the earth begins to thaw.