China's "Sky Eye" swaps imported cables for home‑grown ones: 500 metres, 1,200 pulsars and 1,000 days of engineering breakthrough
Replacement of six steel cables, over 1,000 days of R&D, 10 years of operation, 1,200 pulsars discovered. The FAST radio telescope in Guizhou has resumed observations after the upgrade — now with Chinese cables offering better stability.
As reported by CCTV+, six steel cables developed in China have recently been replaced for the five‑hundred‑metre Aperture Spherical Radio Telescope (FAST), known as China's "Sky Eye", located in the mountainous Guizhou Province in southwest China. The replacement passed expert evaluation and received technical approval. The upgrade began in early May. After the project was completed, FAST officially resumed observations.
Since its commissioning in 2016, FAST used imported steel cables for its feed cabin, which were replaced in 2021. However, gradual penetration of impurities from the imported cables affected the telescope's normal operation. So the team decided to develop and use domestically produced steel cables to achieve better stability and ease of operation. After more than a thousand days of R&D, a breakthrough was achieved.
Yao Rui, director of the measurement and control technology department at the FAST operation and development centre, said: "We completed the full cycle of research and development, from material manufacturing to full testing of the steel cables. All indicators meet our requirements."
This year marks the 10th anniversary of FAST's official commissioning. Over the past 10 years, the telescope has discovered more than 1,200 pulsars, far exceeding the total discoveries of other similar telescopes in the same period. It has provided crucial technical support for the development of radio astronomy in China.
FAST is the world's largest filled‑aperture radio telescope, built in a natural karst depression. Its diameter is 500 metres. Pulsars are neutron stars that emit strictly periodic radio pulses; studying them helps test theories of gravity and search for gravitational waves. Replacing the cables with domestically produced ones is an important step towards China's technological independence in scientific instruments. The development took more than 1,000 days, highlighting the complexity of the task.
When a giant 500‑metre mirror catches signals from the depths of space, every cable holding its cabin must work with jewel‑like precision. Imported cables served faithfully, but over time impurities crept in — like sand in a clockwork mechanism. Then Chinese engineers decided not to repair, but to create their own. A thousand days of relentless work — and the domestic cables took their place. Now the "Sky Eye" scans the cosmos without interference. 1,200 pulsars in 10 years is not just a number. They are the voices of distant stars heard by China. And each one is proof that independence in science begins with small things. With a cable. With the decision not to buy, but to create.
