Astronomical Site Selection Scenarios for Asia

This study aimed to identify and evaluate suitable areas for astronomical observations in Asia using Geographic Information System (GIS) and Multi-Criteria Decision Analysis (MCDA) methods. Our study provides spatial coverage with satellite-based datasets to determine the ideal astronomical areas in Asia for future telescope construction. These datasets were created by adding a digital elevation model (DEM) and artificial light (AL), along with atmospheric data such as cloud cover (CC), precipitation water vapor content (PWV), aerosol optical density (AOD), and wind speed (WS). The dataset was analyzed using a combination of MCDA and GIS techniques. On the continent, the Tibetan Plateau and its surroundings (except the area around 90◦E–35◦N) in northern China were identified as the most suitable areas for astronomical studies with radio telescopes. Suitable areas for infrared and optical telescopes are mainly found in the southeast of the Tibetan Plateau (around 83◦E–31◦N). According to the analysis, an area of 369,096 km2, which corresponds to approximately 0.83 % of the continent, is best suited for infrared observations. Approximately 3.87% of the continent, that is, about 1,725,246 km2, is best suited for radio telescopes, while 0.8 %, that is, 355,842 km2, is best suited for observations with optical telescopes. The Corona-Borealis Observatory (Ngari) is located in the most ideal location for all three scenarios. The findings of this study are of great importance for future plans for astronomical sites on the continent. © 2025 Instituto de Astronomía, Universidad Nacional Autónoma de México.