The Five-hundred-meter Aperture Spherical Telescope (FAST) is a radio telescope located in Pingtang County, Guizhou Province, China. It is the largest single-dish radio telescope in the world, with a diameter of 500 meters. FAST is used for a variety of research projects, including searching for pulsars, studying the Milky Way galaxy, and looking for signs of extraterrestrial life.

In 2020, FAST detected a series of unusual radio signals that were initially thought to be from an extraterrestrial source. However, further analysis showed that the signals were actually caused by interference from a nearby transmitter.

While FAST has not yet discovered any aliens, it is a powerful tool that is capable of detecting very weak radio signals. This makes it a valuable resource for the search for extraterrestrial life.