Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

China's FAST, the world's largest single-dish radio telescope, will greet the third anniversary of operation that began in September 2016.

PINGTANG, Aug. 28, 2019 (Xinhua) --The world's largest radio telescope, the Five-hundred-meter Aperture Spherical Telescope's (FAST), was put into use in a mountainous region of southwest China's Guizhou Province on Sept. 25, 2016.

The telescope, nicknamed Tianyan, or the Eye of Heaven, can accurately image twice as much the sky as the Arecibo Observatory in Puerto Rico, which had previously been the world's largest single-dish radio telescope, with double the sensitivity and five to ten times the surveying speed.

Work on the nearly 1.2 billion-yuan (180 million U.S. dollars) project started in 2011, 17 years after it was proposed by Chinese astronomers.

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Aerial photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)

Photo taken on Aug. 27, 2019 shows China's Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province. (Xinhua/Ou Dongqu)