What are 28 stars?

China constellation system-three walls and twenty-eight hostels

Generally speaking, the framework of China constellation is a system of "three walls and twenty-eight lodges".

We know that the earth revolves around the sun once a year, so it seems to us on earth that the sun moves slowly on the starry background once a year and returns to its original position (of course, we can't see the stars when the sun is high in the sky, but we can infer this by observing the stars around it after sunset or before sunrise). The route we see the sun moving slowly is called the ecliptic. Moreover, the ancients have long discovered that the route taken by the moon and the five planets of gold, wood, water, fire and earth is also near the ecliptic. Because it is necessary to measure the position changes of these moving celestial bodies, the starry sky near the ecliptic is particularly important. So the ancients divided this part of the starry sky into 28 parts along the ecliptic, and each part was called a "night". Together, these 28 constellations are called "28 nights".

Why is it divided into 28 parts? Because the moon also roughly runs in this "belt", but the speed of the moon is much faster than that of the sun, and it takes more than 27 days for the moon to make a circle on the background of stars, so the ancients got a neat number: 28, so that the moon makes a circle a day. 28 can be divisible by 4, so that when the sun goes, it can be divided into four parts, and each part is a season. Listen, the ancients were very thoughtful. Then why is it called "Sue"? "Stay" means "stay" and "stay". The ancients imagined that since these constellations were intended to record the journey of the moon, all the chariots and horses on the earth would travel during the day and stay at night, and it would be better for the moon to do the same, so these constellations were called "small houses" and each "small house" was a "moon station".

When twenty-eight hostels are divided into four parts, they are collectively called "four elephants" and have an animal name. They are:

Oriental black dragon: horn, sound, correlation, room, heart, tail, dustpan;

North Xuanwu: bucket, cow, female, empty, dangerous, house, wall;

Western White Tigers: Kui, Lou, Stomach, Zan, Bi, Gou and Shen;

Southern Suzaku: Well, ghosts, willows, stars, Zhang, wings, birds.

Pale means green, and black dragon means "Qinglong"; Suzaku, according to scholars' research, is a quail; Only Xuanwu is the most special, it is a two-in-one animal image-snake turtle.