The conference held in Leiden, the Netherlands, clearly divided the whole sky into many constellation areas.

The meeting held in Leiden, the Netherlands, clearly divided the whole sky into 88 constellation areas. Constellations have no uniform and precise boundaries. Until 1930, in order to unify the complicated constellation division, the International Astronomical Union divided the sky into 88 official constellations with precise boundaries, so that every star in the sky belonged to a specific constellation.

Most of these official constellations are based on ancient Greek myths handed down from the Middle Ages. In contrast, some widely circulated star combinations are not recognized as official constellations, such as the Big Dipper (see star list).

In the three-dimensional universe, there is no necessary connection between these stars. Their positions on the celestial sphere are similar, but in fact they may be far apart. If humans were in another solar system of the Milky Way, they would see the starry sky completely differently. Since ancient times, people have been interested in the arrangement and shape of stars, and naturally linked some stars with similar positions to form constellations.