A total of 88 constellations in the northern and southern hemispheres were officially named by astronomers. This was established by 1930 International Astronomical Union. The names of these constellations include 14 names, 9 species of birds, 2 species of insects, 29 species of land and water animals, some mythical animals and some inanimate objects. It is worth mentioning that the shapes and names of most constellations are nothing like each other. Probably when the ancients named constellations, they tended to use symbolic methods to name constellations as their favorite animals or mythical figures.
Also, the stars in the same constellation rarely have anything to do with each other, but visually they are very close and the distance from us is very different.
The shape of the constellation is not immutable. Although these stars seem to have been fixed in the same position for the past 3000 years, in fact they have been moving relative to the sun at a speed of up to 10 kilometers per second.
Because they are too far away from us, it is difficult for us to observe the change of their position unless there are 30 thousand years. Because of this action, 50,000 years later, bucket handle of the Big Dipper will bend his hips even more than today. Although the shape of the constellation will change with time, we probably won't change the name of the constellation because of it.
In addition, according to the different seasons and the time when individual constellations reach zenith, the 88 constellations are roughly divided into four groups, namely, spring constellation, summer constellation, autumn constellation and winter constellation.
Why do the starry sky change in spring, summer, autumn and winter? This is because when the earth revolves around the sun, the side facing away from the sun is the starry sky we can see in the season that night. As the earth rotates around the sun, it gradually changes its position, so the starry sky in the background slowly changes.