Audio Guide：

We are surrounded by invisible cosmic rays from the space. They are mainly charged particles from the outer space. When cosmic rays enter the atmosphere, we call them primary cosmic rays; and when they collide with atmospheric particles, they create low-energy cosmic rays, called secondary cosmic rays or tertiary cosmic rays. Because Earth is protected by the atmosphere, the energy of the cosmic rays that reach Earth's surface is very low and does not affect living creatures.

Visitors can examine the cosmic rays in the atmosphere through the flash box.