The moon constellation on the astrolabe does not correspond to the lunar calendar.

The reason why the moon constellation on the astrolabe does not match the lunar calendar is because the moon constellation lookup table is only a rough estimate, which is equivalent to treating each month as 29 days. But in fact, the big month is 30, and the situation should be different every year. Therefore, for the most detailed calculation, a more detailed table must be found. Only the carefully searched moon constellation will be accurate, otherwise it will be easy to make mistakes.