What do the nine purples in the Japanese Wei Zi Star Plate stand for?

In the calendar, the nine planets and nine purple refer to nine planets.

There is a theory of the Big Dipper in astronomy. Their rankings are White Wolf, Black Giant Gate, Three Green Wen Qu, Huang Wu Lian Zhen, Six Baiwuqu and Seven Red Pojun. These seven stars are called the Big Dipper, and there are two stars between Pojun, bucket handle and Wu Qu. One star is right-handed, the other is common in Zuo Fu, and Zuo Fu ranks eighth and right.

Nine planets in geomantic omen: Legend has it that one is white, two is black, three is green, four is green, Huang Wu is six is white, seven is red and eight is white, and nine purple is white. The nine planets in Taoism refer to zenith, Tian Rui, Tian Chong, Tianfu, Heaven, Tianxin, Tianzhu and Renxing. Others call the Big Dipper the nine planets after adding Zuo Fu and Youbi.

The historical origin of the nine planets:

The nine planets originated from the ancient people's natural worship of ancient stars, which is the product of the combination of ancient mythology and astronomy.

According to the Book of Changes, the nine planets use the laws of "river map" and "Luo Shu" to calculate all kinds of good and bad luck of geographical feng shui, and use the nine planets to summarize the universe. Therefore, we must know the orbits of the nine planets to understand the reason of "Heluo".

Refer to the above content: Baidu Encyclopedia-Nine Planets