Why was FAST built in a natural depression in Guizhou, China?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Telescope Aerial view of the Keck Observatory's twin domes, which are opened to reveal the telescopes. Keck II is on the left and Keck I on the right.

The FAST (Five-hundred-meter Aperture Spherical Telescope) was constructed in the Dawodang depression in Guizhou, China, primarily to accommodate its massive size. With a diameter of 500 metres (1,600 feet), the telescope is a spherical reflector that is too large to be moved or tilted as a single unit.1

By utilizing a natural depression, engineers were able to provide a stable, pre-existing basin to support the immense structure of the dish. Because the dish itself remains stationary, the telescope achieves its ability to observe the sky by adjusting the shape of its surface and moving a suspended feed cabin to focus incoming radio waves.1