QTT 110-meter Radio Telescope Completes Three-Layer Antenna Mount Assembly in Qitai
On August 18, in Qitai County, Changji Prefecture, Xinjiang, the final diagonal beam was hoisted into place, marking the precise closing of the three-layer azimuth mount of the 110-meter fully steerable Qitai Telescope (QTT). This milestone means the reflector can now rotate 360° around the vertical axis, supported by a structure carrying over 3,000 tons of pitch-rotating components. China's first 100-meter-class fully steerable radio telescope has moved from blueprint to physical reality.
Key Figures
- 6,000 tons: total steel structure weight of the telescope, with the azimuth mount supporting 3,000+ tons of rotating components at arcsecond-level precision—described as "identifying a ping-pong ball from 3.3 km away."
- 110 meters: diameter of the primary reflector.
- Construction began September 2022; main body completes 2027; full operation expected 2028. Once complete, QTT will be the world's highest-precision, highest-frequency 100-meter-class fully steerable radio telescope under construction.
- Dark matter detection (pulsar timing array gravitational effects)
- Galactic structure and evolution (neutron star–white dwarf binary dynamics)
- High-precision pulsar timing (nanosecond stability, potentially contributing to a pulsar time standard for satellite navigation)
- Low-frequency gravitational waves (complementing LIGO-Virgo)
- Precise localization of fast radio bursts (FRBs)
- Black hole accretion disk dynamics
- Searches for prebiotic molecules related to life's origins
The contractor is CETC's 39th Research Institute. Site lead Ma Wengang called the milestone "fitting the giant observing eye with strong arms." Antenna system chief engineer Xu Qian attributed the precision to three foundations: an advanced reflector system, ultra-wideband data reception, and high-precision rapid measurement with coordinated control.
Why Qitai, and Why 110 Meters
Qitai, on the northern slopes of the Tianshan Mountains at the southeastern edge of the Junggar Basin, combines favorable altitude, terrain, and a quiet electromagnetic environment—sparse population, radio quietness, and dry climate. Researcher Yuan Lanfeng of USTC's Hefei National Research Center told Global Times this is a core endowment for astronomical observation: remoteness lets the telescope hear the universe's faintest signals.
The 110-meter steerable design is also crucial: FAST is 500 meters across but its feed cabin passively receives signals and cannot quickly track moving objects. QTT can actively rotate to track high-speed targets, space debris, and deep-space spacecraft. Together, FAST acts as a "quietly listening ear" while QTT is a "turning eye," turning Chinese radio astronomy from a single point into a two-node network.
Science Targets
Per CAS and CCTV disclosures, by priority:
The Bigger Picture
FAST, completed in 2016, recently finished an overhaul replacing imported cables with domestically made ones, and had discovered 1,152 new pulsars as of last October—more than all other international telescopes combined over the same period. QTT complements FAST with a "precision + frequency + active tracking" combination: FAST discovers broadly, QTT follows precisely.
Internationally, the SKA (Square Kilometre Array) begins science operations in 2029, and MeerKAT has already delivered record-breaking observations such as an 8-billion-light-year hydroxyl megamaser. QTT's 2028 launch aligns with SKA's first wave of scientific output, positioning China to contribute independent, higher-precision radio samples for cross-validation rather than remaining a bystander.
Much remains: the elevation mount, reflector panels, feeds, low-noise receivers, ultra-wideband terminals, control systems, and high-precision actuators. But with the August 18 mount closing complete, the skeleton stands, and the 2027 main-body completion looks assured.
2028 will mark the inflection point when Chinese radio astronomy moves from a "single star instrument" to a networked system.
Sources: Xinhua/CCTV News 8/21, Global Times 8/18, CCTV.com 8/18, Huagong Yiqi 2026 No. 27, CAS FAST pulsar statistics (October bulletin), CETC 39th Research Institute site lead Ma Wengang, antenna system chief engineer Xu Qian.