The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is constructed
in a karst (or natural sinkhole) in Guizhou Province in south-western China.
The surface of the telescope is made of 4450 triangular perforated-aluminium panels, 11m on each side.
The panels are supported by a mesh of steel cables.
When the telescope is in operation, radio waves are focused to a receiver in a cabin suspended 140m above the dish surface.
In the image above, the cabin has been lowered to the surface of the dish.
The structures protruding above the dish surface are part of the system which enables the surface accuracy to be monitored and controlled.
This
ADAP image from 2015 shows an early stage of the telescope construction.
The telescope is currently being commissioned and will ultimately be outfitted with receivers
covering frequencies from 70 MHz to 3 GHz. CSIRO has built a
19-beam multi-beam receiver for the telescope.