China Switches on the World’s Largest Radio Telescope

Measuring 1,640 feet across, the massive device will scour the skies for signs of life and new galaxies

Chinese Radio Telescope
Chinese Academy of Sciences

After over two decades of planning and five years of construction, the world’s largest radio telescope is finally complete. Yesterday, it was switched on for the first time, Gillian Wong reports for the Associated Press.

Named the Five-hundred-meter Aperture Spherical Telescope (FAST), the parabolic dish is nestled in a natural depression in Pingtang County, a mountainous region of Guizhou Province in south central China, which naturally protects against radio interference. The device cost $180 million and more than 8,000 people in eight villages within a three-mile radius of the facility had to be relocated, adding up to another $269 million.

The telescope, nicknamed Tianyan, or Eye of Heaven, is constructed from 4,450 aluminum panels with a 1,640-foot diameter. It surpasses the 300-meter Arecibo Observatory in Puerto Rico for the title of the world’s largest. Tianyan is not only larger than Arecibo, it’s also much more sensitive, according to Adam Born at Wired. That’s because FAST has built-in adjustable reflectors that can be tuned to compensate for signal deformations. While Arecibo can scan about 20 degrees of the sky, FAST looks at 40 degrees and will scan the sky at five to ten times the speed.

“Once completed, FAST will lead the world for at least 10 to 20 years,” Yan Jun, director general National Astronomical Observatories of China, the agency that built and runs the telescope, says in a press release.

Wong reports that the telescope will search for signs of extraterrestrial life, gravitational waves and detect stars and galaxies we have not yet discovered. “The ultimate goal of FAST is to discover the laws of the development of the universe,” Qian Lei, an associate researcher with NAOC.

Chris Buckley and Adam Wu at The New York Times also report that the telescope is a prestige play for China, which has taken an uncomfortable back seat to western science in the last century. The telescope is a signal to the international research community that China wants to make its mark in the field. China excelled at astronomy in its history. “Now we’re racing to catch up and want to recreate the glories of our ancestors by reviving our astronomy,” Zhang Chengmin, an astrophysicist at NAOC tells Buckley and Wu. “China isn’t just an economic power; it is also becoming a scientific power.”

Rebecca Morelle at the BBC says it will take three years to fully calibrate the massive detector. Even so, on one of its first debugging test runs the telescope received a signal from a pulsar 1,351-light years away, Wong reports. Once the telescope operators confirm that the massive detector works properly, they will begin accepting proposals for projects from researchers around the world with hopes that FAST will live up to its acronym, quickly making discoveries.

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