PINGTANG, June 30, 2016 (Xinhua) -- Photo taken on Dec. 16, 2015 shows a working staff working at the construction site of the Five-hundred-meter Aperture Spherical Telescope, or "FAST," in Pingtang County, southwest China's Guizhou Province. FAST, the world's largest ever radio telescope, has a dish-like reflector, which is 500 meters in diameter and made up of 4,450 panels. Now technicians have assembled 4,443 panels, accounting for 99.8 percent of all. The assembling work of the reflector will be completed on July 3. The telescope will be used to detect and collect signals and data from the universe. (Xinhua/Ou Dongqu)