Two radio telescopes with antennas with a diameter of 40 meters, one of which is located in the northeast and the other in the southwest of China, were put into operation on Friday. These telescopes will help in the exploration of deep space and unraveling cosmic mysteries.
The two telescopes were built by the Shanghai Astronomical Observatory (SAO) of the Chinese Academy of Sciences (CAS) in the Changbai Mountain area in northeastern China’s Jilin Province and in Shigatse in southwestern China’s Xinjiang Autonomous Region, respectively.
With the deployment of the two new telescopes, China’s very long wavelength interferometry (VLBI) network now includes one control center in Shanghai and six stations in Shanghai, Urumqi, Kunming, Changbai Mountain and Shigatse, SHAO said.
VLBI is a radio interferometry technology that can be used to obtain fine radio images and precise positions of space objects. In addition, it can provide highly accurate positioning of space probes in deep space. Unlike traditional methods, the VLBI method can combine signals from different telescopes for joint processing. In other words, it is a “virtual telescope” whose size is equal to the maximum distance between the telescopes, the scientists explain.
Thanks to the two new telescopes, the longest baseline of China’s VLBI network, or “effective aperture of the virtual telescope,” has been extended from about 3,200 kilometers to about 3,800 kilometers, said Shen Zhiqiang, chairman of SHAO.
As a result, the observing area of China’s upgraded VLBI network can be expanded by 25 percent and the angular resolution in the X-band can be improved by 18 percent, according to Mr. Shen.
China’s VLBI network supported the Chang’e-1 to Chang’e-6 lunar exploration missions and the Tianwen 1 Mars mission, providing high-precision measurement information on the orbits and positions of spacecraft.
Such a Chinese VLBI network with six stations will allow simultaneous measurements and flexible tracking of multiple targets in different celestial regions, which will provide more powerful support for lunar and deep space exploration missions in the future, Shen said.
At the launch ceremony of the two telescopes on Friday, Ding Chibiao, vice president of CAS, emphasized the crucial role of core science and technology infrastructures in supporting innovation and called for promoting the openness and sharing of science and technology facilities.
Ye Shuhua, CAS academician, said that the two new telescopes will play an important role in future lunar exploration, as well as deep space missions to study asteroids, Mars, Jupiter and other celestial bodies.
The construction of the two telescopes, which began in September 2023, was fraught with great challenges. One telescope was built at an altitude of 4,100 meters, while the other was located in a cold region where winter temperatures can drop below minus 20 degrees Celsius, according to Shen.
The two telescopes will expand China’s capabilities in radio astronomy research and contribute to advanced astronomical studies such as supermassive black holes, compact astrophysical objects with rapid variability, electromagnetic analogs of gravitational waves and galactic dynamics, Shen added.
