Why is the auspicious day different every month in the yellow calendar?

The so-called auspicious days of the ecliptic are all artificially fabricated and have no scientific basis. Of course, each said his own words. Almanac can only be used as a reference, not to be trusted. Just as Tathagata is an Indian, so is his image. Jesus has many westerners, so his image has become a westerner with a high nose and deep purpose. They are all artificial.