Please briefly talk about why humans want to build a lunar navigation satellite system.

It is convenient for the communication between the moon and the earth and the control of the lunar lander.

The moon, the name of the celestial body, is called the moon as seen by the naked eye. In ancient times, it was also called Taiyin, Xuantu, Chanjuan and Pan Yu. It is a satellite of the earth and the fifth largest satellite in the solar system.

Global Positioning System (GPS) is a new generation of space satellite navigation and positioning system jointly developed by the United States Army, Navy and Air Force in 1970s. Its main purpose is to provide real-time, all-weather and global navigation services for land, sea and air, and it is also used for some military purposes such as intelligence gathering, nuclear explosion monitoring and emergency communication. It is an important part of America's global dominant strategy. After more than 20 years of research and experiments, it cost 30 billion dollars. By1March 1994, 24 GPS satellite constellations with global coverage of 98% had been deployed.