Why are the "twelve constellations" not determined according to the lunar calendar?

Answer: Because the constellation was introduced to China from abroad, there was a saying in ancient China that the constellation was called the zodiac, which divided the zodiac into twelve parts, so it was called the "zodiac". In the culture of China, the "Zodiac" is also calculated according to the lunar calendar algorithm, and the ancient calendar tables in China are all based on the lunar calendar.