Construction of FAST began in the south-western province of Guizhou in 2011, and it is situated in a natural crater-like feature called a karst that is ideal for housing the colossal concave disc.

“The size of this telescope is key to its scientific impact,” says Tim O'Brien at the University of Manchester in the UK. “The bigger the telescope, the more radio waves it collects and the fainter objects it will be able to see.”