The variations of the azimuths for the sunrise and sunset observed by him "created 10 days", that is, created the ten-month solar calendar which is just realistic.

羲和观测太阳出没方位变化而“生十日”、即制订产生十月太阳历才符合事实。

youdao

It takes place on the nearest Friday to the seventeenth day of the month of Mehr, according to the solar-agricultural calendar.

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