The world's largest radio telescope in China has received its first signals from space and begun a three-year testing phase.
Five Hundred Metre Aperture Spherical Telescope (FAST), which measures 500 meters or 1,640 feet across, was opened on Sunday. Construction was completed back in July.
It will take three years to calibrate the instrument so it can become fully operational. FAST is located in a natural crater in Guizhou Province, southwest China. It took five years and $180 million to complete.
It dwarfs the former largest radio scope, the Aricebo Observatory in Puerto Rico, which has a diameter of 305 metres.
The huge size allows it to collect signals from the far reaches of space.
China is serious about its space program. It launched its second space lab, the Tiangong-2, earlier this month. It lost control, however, of its first which will crash into Earth's atmosphere next year.
China plans to have a manned space station by 2022.