There are 88 constellations. Constellation is one of the essential components of astrology, and it is also a group of stars in the sky. Since ancient times, humans have linked three or five groups of stars with their mythical characters or instruments, known as "constellations".
Constellation is a means to determine the sky position in almost all civilizations, and is widely used in the field of navigation. The division of constellations is completely artificial. Different civilizations have different divisions and names.
There was no uniform precise boundary for constellations until 1930. In order to unify the complex constellation division, the International Astronomical Union divided the sky into 88 official constellations with precise boundaries, so that each star in the sky belongs to a specific constellation.
Most of these official constellations are based on ancient Greek mythology handed down from the middle ages. In contrast, there are some widely circulated star combinations that are not recognized as official constellations, such as the Big Dipper.
In the three-dimensional universe, these stars do not necessarily have a practical relationship with each other, but their positions on the spherical shell surface of the celestial sphere are similar, but in fact they may be far away from each other. If humans were in another solar system in the Milky way, the starry sky they reached would be completely different. Since ancient times, people have been interested in the arrangement and shape of stars, and naturally connect some stars with similar positions to form constellations.