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FAST (Five Hundred Meter Aperture Spherical Telescope) is a large radio telescope in Guizhou, China, which saw first light in 2016 and reached full operational in 2020, the largest single-dish telescope in the world. It is similar to Arecibo Observatory (a very large stationary dish pointed straight up, situated in a depression in the ground) but with the ability to aim further from the zenith: to 40° from zenith compared to Arecibo's 20°. The dish is 500 m across (Arecibo's was 305 m), but any observation uses 300 m, the additional size allowing pointings away from the zenith that still have a collecting area 300 m in diameter. Though it has spherical in its name, it deforms the reflector into a parabolic shape directed at its target. It has nine feeds spanning 70 MHz to 3 GHz.