China's gigantic telescope embraces int'l exchanges, innovative development

This photo taken on Feb. 27, 2024 with infrared camera shows China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST) under maintenance in southwest China's Guizhou Province. [Photo by Ou Dongqu/Xinhua]

China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST), the world's largest single-dish radio telescope, has identified more than 900 new pulsars since its launch in 2016. The number of new pulsars discovered by FAST is more than three times the total number of pulsars found by foreign telescopes during the same period, Han Jinlin, a scientist with the National Astronomical Observatories under the Chinese Academy of Sciences (NAOC), said on Wednesday. One of the important implications of the research on pulsars is to provide cosmic coordinates for possible future interstellar travel, Han noted. FAST started formal operations in January 2020 and was officially opened to the world in March 2021. The telescope provides astronomers around the globe with a powerful tool to uncover the mysteries and evolution of the universe, said Jiang Peng, chief engineer of the FAST.

SCIENTIFIC COOPERATION
British astronomer Ralph Eatough, who has been interested in Chinese culture, history and literature since he was young, said that he felt extremely lucky to travel to China and join the FAST research group, the members of which have been very welcoming. Having earned a doctorate in pulsar astrophysics at the University of Manchester, Eatough works as a pulsar astronomer at the NAOC and takes charge of pulsar data processing and time-frequency system optimization. Pulsars are extremely compact remnants of massive stars that, whilst spinning extremely quickly (sometimes hundreds of times a second), emit beams of electromagnetic radiation that can sweep past the Earth -- a bit like a cosmic lighthouse, he said. Thanks to its high sensitivity, the telescope can detect very faint pulsars that were previously too far away to identify.
In the past few years, Eatough has joined Chinese scientists and performed many observations with FAST, searching for undiscovered pulsars and precisely measuring the properties of pulsars found with FAST. He has been searching for pulsars in the small satellite galaxies surrounding the Milky Way. "These would be the most distant pulsars known, and it is only now with the sensitivity of FAST that we have the chance to detect them. Such pulsars could tell us a lot about the unmeasured gaseous material that surrounds the Milky Way," Eatough said. Eatough said that opening up FAST to the world means that now astronomers can perform experiments that were previously not possible due to insufficient telescope sensitivity, with a prime example of this being the potential to detect pulsars located in external galaxies.
According to Sun Chun, engineer in charge of FAST measurement and control, FAST has received applications from 15 foreign countries, including the United States, Germany and Japan, and approved a total of nearly 900 hours for observation. The applications mainly involve fast radio burst observations, pulsar observations, and neutral hydrogen surveys, Sun added.

TOURISM EXCHANGE
The telescope has attracted many tourists from home and abroad since its inception. The telescope, located in a naturally deep and round karst depression in southwest China's Guizhou Province, has a reception area equal to 30 standard football fields. This February, a total of 34 people from a French delegation, including students, young volunteers and staff members from the Secours populaire français, visited the telescope and the memorial hall dedicated to the late chief engineer of the FAST project, Nan Rendong.
It was the first time for Florent Madrolle, a French translator, to visit China and see the gigantic telescope. "The size and the technology were very impressive," said Madrolle. Five kilometers away from FAST in Kedu Township, the memorial hall has attracted a lot of tourists and visitors eager to pay tribute to Nan. Nan, who selected the site of FAST and oversaw its construction, died in 2017 due to sickness at the age of 72. China honored him with several posthumous titles, including the "role model of our times." Thibouw Laurine said that during this trip, she not only saw the telescope and knew its functions, but was also deeply touched by and eager to know more stories about Nan.

TECHNICAL INNOVATION
Since its inception, the telescope has continually prompted special technical progress through the efforts of a team of scientists led by Jiang. "I thought we would revise the design scheme seven or eight times, and didn't expect that the first version would be so successful, with its performance reaching the globally advanced level," said Chai Xiaoming excitedly, senior engineer at the NAOC. She pointed at a silver-plated low-noise amplifier (LNA), which was only the size of a harmonica. The LNA is the core component of the telescope's receiver. It had been imported from foreign countries including the United States, Sweden and Australia previously. To master the key technology, Chai and her team spent nearly two years developing a high-performance domestic low-noise amplifier. As soon as the prototype of the LNA was launched, it attracted the attention of the international astronomical community. The Brazilian BINGO project contacted the telescope's operation and development center for batch purchase of the LNA.
Chai said that if the cooperation is reached, it would be the first time that the core components, independently developed by the telescope's operation and development center, are exported overseas. The FAST project had no experience to follow and was destined to meet unprecedented challenges. "No one told you what to do, and no one was sure what would work," said Jiang, adding that the construction stage was filled with trials and failures. Jiang said that if FAST was only regarded as a telescope or a piece of observational equipment, it would have already sufficed. But to maintain its leading position in the world, his team will make every effort to ensure that the FAST becomes even more stable and more efficient.

A drone photo taken on Feb. 26, 2024 shows China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST) under maintenance in southwest China's Guizhou Province. [Photo by Ou Dongqu/Xinhua]

At present, the annual observation time of the telescope is about 5,300 hours, and it plays an important role in the continuous output of scientific research achievements. In the near future, the telescope will provide the international astronomical community with new perspectives, allowing them to further explore the universe and try to find the unknown, and make greater contributions to helping human beings break into new fields of cognition, Jiang added.

Edited by Wang Miao 

with reference to <https://english.news.cn/20240417/d22aa606aaae4d77adc048d23202e587/c.html>