How big is the artificial moon and what is its use?

1. The artificial moon is 20 meters in diameter and the spot is 4000 meters in diameter. When it flew over western Europe, just after midnight, it generously shot the first ray of sunlight to the ground.

2. It can solve the lighting problem in high latitudes of Russia. In these areas, there is always a systematic night every year, and people who are eager for light suffer greatly. In addition, the space mirror can also be used to illuminate areas where natural disasters such as earthquakes or floods occur, so as to carry out rescue work at night. But some people have raised objections to this. Biologists worry that it will change the biological pattern in some parts of the earth. Astronomers, on the other hand, strongly object that this may affect astronomical observation. But Russian scientists think that artificial moon is a very useful attempt, so they have implemented a series of plans codenamed "Flag".