QTT 110m Fully Steerable Radio Telescope Completes Three-Layer Azimuth Pedestal Assembly

Forum topic · QianXun · 2026-08-23

Summary

On August 18, the Qitai 110-meter Radio Telescope (QTT) in Qitai County, Changji, Xinjiang, achieved a key construction milestone: the three-layer azimuth pedestal was precisely mated, locking the 3,000+ ton elevation-rotating structure onto a 6,000-ton steel skeleton. Built by the 39th Research Institute of China Electronics Technology Group, the antenna uses a fully steerable design reaching arcsecond-level surface accuracy—equivalent to recognizing a ping-pong ball at 3.3 km. Construction began in September 2022, with main structure completion targeted for 2027 and full operations in 2028. Once operational, QTT will be the world's highest-precision and highest-frequency 100m-class fully steerable radio telescope, complementing FAST's 500m fixed dish with active tracking of fast-moving targets, near-Earth asteroids, and deep-space missions including Chang'e, Tianwen, and asteroid defense.

Key points

Construction milestone

On August 18, in Qitai County, Changji Prefecture, Xinjiang, the three-layer azimuth pedestal of the Qitai 110m Radio Telescope (QTT) was precisely mated as the final inclined beam was hoisted into place.
The 3,000+ ton elevation-rotating section is now supported by a total steel skeleton weighing about 6,000 tons, enabling 360° rotation around the vertical axis.
The telescope is China's first 100m-class fully steerable radio telescope.

Scale and precision

6,000 tons total steel structure; 3,000+ tons in the elevation section.
Arcsecond-level pointing accuracy, described as recognizing a ping-pong ball at 3.3 km distance.
Main reflector aperture: 110 meters.
Built by the 39th Research Institute of China Electronics Technology Group (CETC-39). On-site project lead Ma Wengang described the milestone as "fitting a sturdy arm onto the giant eye." Chief antenna engineer Xu Qian attributed the precision to three foundations: an advanced reflector system, ultra-wideband data reception, and high-precision rapid measurement and coordinated control.

Timeline

Construction started: September 2022.
Main structure completion: 2027.
Full operation: 2028.
Once online, QTT will be the highest-precision and highest-frequency 100m-class fully steerable radio telescope under construction worldwide.

Site selection rationale

Qitai is located on the northern slopes of the Tianshan Mountains, southeast edge of the Junggar Basin.
The site combines low population density, a radio-quiet electromagnetic environment, and dry climate.
Yuan Lanfeng of USTC's Hefei National Research Center for Microscale Matter described these as core endowments for radio astronomy.

Why 110m fully steerable matters

FAST (500m) has a passive feed cabin and cannot rapidly track moving celestial objects.
QTT can actively slew, enabling tracking of high-speed targets, space debris, near-Earth asteroids, and deep-space spacecraft.
The two telescopes together form a dual-node Chinese radio astronomy network: FAST as a "static listening ear" and QTT as a "turning eye."

Scientific targets (ranked by disclosed priority)

Dark matter detection via pulsar timing array gravitational effects.
Galactic structure and evolution through neutron star–white dwarf binary dynamics.
High-precision pulsar timing (nanosecond stability) for an integrated pulsar timing array to calibrate satellite navigation clocks.
Low-frequency gravitational waves, complementary to LIGO-Virgo.
Precise localization of fast radio burst (FRB) sources.
Black hole accretion disk dynamics.
Searches for prebiotic molecules related to the origin of life.

National mission support

Follow-on Chang'e lunar missions (after CE-6).
Mars exploration: Tianwen-2 and Tianwen-3.
Asteroid defense, including rapid response to objects such as 2024 XA1.
Outer solar system exploration.
QTT is positioned as a ground-based node in China's 2030 deep-space exploration network.

Strategic context

FAST, completed in 2016, recently completed a major cable system retrofit with the first six domestically produced giant steel cables replacing imports. As of October last year, FAST had discovered 1,152 new pulsars, exceeding the combined total of other international telescopes during the same period.
FAST excels at wide-area survey and discovery; QTT excels at precise follow-up, fast tracking, and higher frequencies.
Internationally, SKA (Square Kilometre Array) begins science operations in 2029; MeerKAT has already delivered records such as hydroxyl megamaser detections at ~8 billion light-years. QTT's 2028 timeline aligns with SKA's first science outputs, allowing China to contribute independent, higher-precision radio samples for cross-validation.

Remaining work

Elevation frame, reflector panels, feed cabin, low-noise receivers, ultra-wideband data terminals, observatory master control, data and network systems, and high-precision actuators are still to be installed.

Significance

The August 18 mating completes the skeleton; 2027 main structure completion is on track.
2028 marks China's transition from a single-instrument radio astronomy program to a networked system.

References

Xinhua News Agency / CCTV News, August 21
Global Times, August 18
CCTV.com, August 18
Chemical Instruments Network, 2026 Issue 27
CAS FAST pulsar statistics bulletin, October
On-site interviews: Ma Wengang (CETC-39 project lead), Xu Qian (chief antenna engineer)