Xinhua

China on Sunday began using the world's largest radio telescope to survey the heavens and listen for signals of possible extraterrestrial life.

Nestled in a valley surrounded by naturally formed karst hills in China's southern Guizhou province, the Five-hundred-meter Aperture Spherical Telescope (FAST) measures 500 meters in diameter, dwarfing the 305-meter Arecibo Observatory in Puerto Rico, the previous record holder for largest telescope. The telescope, which took five years and $180 million to build, has 4,450 11-meter-long (36-foot) panels that reflect interplanetary radio waves to the massive 30-ton retina suspended in the middle.

Astronomers will use the telescope to survey the Milky Way and other galaxies, detect faint pulsars and listen for signals from possible extraterrestrial civilizations, according to researchers at the National Astronomical Observatories (NAO) at the Chinese Academy of Sciences.

"FAST's potential to discover an alien civilisation will be five to 10 times that of current equipment, as it can see farther and darker planets," the NAO's Peng Bo told China's official Xinhua news agency when construction on the radio telescope was completed in July.

Besides the time and money spent, there was also human cost to the massive project. China said more than 9,000 people are being required to leave their homes to make space for the telescope and its support facilities, according to state-run Xinhua News Agency.