The astronomical observatory project currently under construction is said to be the largest in both China and Asia, showcasing the country’s ambition to explore space.
The facility is located on Saishiteng Mountain in Lenghu Town, which is part of the Haixi Mongol and Tibetan Autonomous Prefecture in Qinghai Province. Scientists chose this location due to its altitude of approximately 4,200 meters above sea level and its consistently clear night sky with low light pollution. Saishiteng is regarded as one of the most ideal astronomical observation sites in the world.
“After three years of continuous data collection, we found that the average visibility here is 0.75 arc seconds,” said lead researcher Deng Licai from the National Astronomical Observatories of China (NAOC), affiliated with the Chinese Academy of Sciences (CAS).
Saishiteng, a very steep mountain with barren land, poses significant challenges for construction. Just to select a site and find a route to the top, scientists had to climb for three to four hours each time.
During the initial phase of construction, everything had to be transported to the mountain top by helicopter, with 80 flights per day if weather conditions allowed.
Engineers have now completed the installation of the two initial monitoring towers of the Lenghu astronomical observatory—one tower for studying the Sun and the other for observing stars at night. Every day, data will be automatically sent to NAOC.
According to plans, more than 30 telescopes will be installed on Saishiteng Mountain, including the Wide Field Survey Telescope (WFST). This 2.5-meter diameter instrument, featuring advanced primary focus optical design, high resolution, and wide field of view, will allow for the scanning of the entire Northern Hemisphere in just three nights.
Additionally, an 0.8-meter diameter atmospheric spectroscopy telescope is also being installed by the Institute of Geochemistry and Geophysics (IGG) under CAS. It will coordinate efforts for deep space exploration missions, including observations of Mars, Jupiter, comets in the Solar System, and small celestial bodies, providing independent observational data as well as searching for and identifying exoplanets.
To preserve the dark sky for observational purposes, the Haixi Mongol and Tibetan Autonomous Prefecture government has revamped the street lighting system to reduce light pollution, while also enacting regulations to protect the clear atmosphere in the area.
The Lenghu astronomical observatory project. (Video: CCTV+).
