Giant radio telescope to reach even farther

China will finish upgrading the world’s largest single-dish radio telescope next month to help scientists discover more stellar objects that are unique and farther from Earth, according to a project insider.

The Five-hundred-meter Aperture Spherical Radio Telescope, known as FAST, has had more precise and efficient signal receivers installed, said Liu Oufei, deputy chief engineer of the telescope’s receiver and terminal systems.

The upgrade includes a more advanced 19-beam receiver system to replace the current single-beam receiver, which was easier to calibrate when FAST was launched in 2016, he said.

“Previously, it was like having only one ear listening to the sky for cosmic signals,” he said. “Now we have 19 ears, which can significantly increase our efficiency and ability to detect farther and fainter signals.”

The new receiver will be at least six times more accurate than, and can survey the night sky 19 times faster, drastically shortening the time needed for data collecting, he said. Before it had usually taken around 20 days to survey the sky.

Scientists also are looking at setting up smaller radio telescopes around FAST to create a telescope array with greater resolution and data accuracy, Liu said.

The surrounding telescopes would consist of two to 10 radio telescopes measuring 30 or 50 meters in diameter, and resolution of the array would be about 100 times greater than now, according to proposals from the FAST observation station of the National Astronomical Observatories of China, part of the Chinese Academy of Sciences.

Now we have 19 ears, which can significantly increase our efficiency and ability to detect farther and fainter signals.”

Liu Oufei, deputy chief engineer of receiver and terminal systems for radio telescope

“We have the engineering know-how to achieve these goals, but it ultimately comes down to the scientists and their projects to determine whether new telescopes are necessary,” Liu said. “Everything regarding the expansion is still in its early stages and is subject to change.”

Located in a natural depression in Guizhou province, FAST consists of 4,450 triangular panels that form a receiving dish about the size of 30 soccer fields.

FAST’s main missions include finding and studying pulsars, which are superdense, superbright rotating remnants of massive stars that eject beams of powerful electromagnetic radiation from their poles.

The beams are so bright that scientists can detect them millions of light years away, hence pulsars are called “the lighthouse of the galaxy,” Liu said.