Audio Guide：

A professional observatory needs to be built at an appropriate location. Firstly, there must be no light pollution and air pollution, which is a basic requirement. Then, the number of clear nights must be high, and there must be good field of vision, low humidity and high altitude. The best three observatories now in the world are located on a volcanic mountain top in Hawaii, on a plateau in Chile in South America, and on the Canary Islands off the coast of northern Africa.

Visitors can learn more about the observatories around the world through the hemispherical projection with a touch screen.