BEIJING — More than 9,000 Chinese villagers are leaving their homes to make way for aliens — or for the possible echoes of them, at least.

It is not a colonization plan from outer space. The Chinese government is relocating the villagers as it finishes building the world’s biggest radio telescope, one of whose purposes is to detect signs of extraterrestrial life.

The telescope will be 500 meters, or 1,640 feet, in diameter, making it by far the largest instrument of its kind in the world. It is called FAST, short for 500-meter aperture spherical telescope, and will cost an estimated 1.2 billion renminbi, or $184 million, to erect. The government hopes to complete it by September.

The mass relocation was announced on Tuesday in a report by Xinhua, the state news agency. The report said officials were moving 2,029 families, a total of 9,110 people, who live within about three miles of the telescope in the area of Pingtang and Luodian Counties in the southwestern province of Guizhou. Depopulating the area will create “a sound electromagnetic wave environment” for the telescope, Xinhua said.