The 500-meter spherical radio telescope (FAST) is like a bowl. What will happen if it rains?

The 500-meter spherical radio telescope (FAST) is the largest radio telescope in the world at present, with a diameter of 500 meters, like a huge football field. The sky looks like a container, but its reflector is not a smooth mirror, but a steel plate with many holes, just like a huge sieve. It can be said that the design of so many small holes is aimed at not storing rainwater.

However, some people still think that if it rains heavily, the fundus can't be completely smooth, and there will always be bumps, which will lead to poor drainage of rainwater. Then, water will inevitably exist, and the accuracy of the eyes will also be affected.

This idea is basically unfounded, because this problem has been thought of when designing such a huge eye project. Therefore, in the design, the drainage problem is the key design problem. In order to smooth drainage, people initially designed and built the tunnel drainage project.

The design scheme of pressureless tunnel is mainly adopted. The drainage tunnel in the eye structure is1121m. In order to highlight the drainage effect, the tunnel is divided into two sections, one is an open-cut section with a length of 58.588 m, and the other is an open-cut section with a length of1062.499m.. This kind of light and dark tunnel ditch design can basically solve the drainage problem of the eye in rainstorm weather.

The Eye of Heaven can not only resist stagnant water in design, but also shelter from rain in geographical location. Because the Eye of Heaven is located in Dawodang, Kedu Town, Qiannan Prefecture, China Province, the terrain belongs to a typical karst landform, and the rainwater permeates quickly and is not easy to gather, so the general rain has little influence on the Eye of Heaven. But if it is a rainstorm, the drainage system will come in handy.