China’s Meridian Project (CMP), one of the country’s major scientific initiatives, completed acceptance checks for its second phase on Friday. According to the National Space Science Center of the Chinese Academy of Sciences, this advancement will enhance scientific research and strengthen the nation’s ability to forecast space weather.
Known as the Ground-based Space Environment Monitoring Network (CMP), it is the first of its kind to monitor Sun-Earth space comprehensively, spanning from the Sun’s atmosphere to the area near Earth.
Solar-terrestrial space is the primary zone for human space activities. Extreme space weather can cause serious problems, including satellite malfunctions, communication breakdowns, navigation errors, and power outages. Because of this, accurate space weather predictions and early warnings are essential.
The National Space Science Center leads the project. The first phase began in 2008 and was finished in 2012, while the second phase started construction in November 2019. It now includes over 30 observation stations across China and the polar regions.
The CMP provides detailed tracking and monitoring of solar storms, from their origin in the Sun’s atmosphere to their effects near Earth. This supplies China with critical, self-sufficient data for weather forecasting and supports advanced scientific studies, such as the dynamic changes in Sun-Earth space and the basic processes of space physics.
The second phase of the project includes several advanced tools. Among them is the Daocheng Radio Telescope, which captures 3D images of the Sun’s corona up to 10 solar radii. It also features a lidar array that continuously measures atmospheric helium from 200 to 1,000 km altitude. Another highlight is the world’s first tristatic incoherent scatter radar system, capable of ionospheric tomography and 3D imaging over thousands of kilometres.
Other additions include the Chinese Dual Auroral Radar Network (CN-DARN), a mid-latitude radar system that monitors ionospheric activity in Asia’s middle and high latitudes. This fills a gap left by previous systems like SuperDARN. Also, for the first time, China now has a system dedicated to creating 3D models of solar wind structures, aiding in interplanetary environment forecasts.
During its trial run, CMP-Phase II gathered and shared data globally. For example, it observed the super geomagnetic storm in May 2024, documenting the Sun-Earth space environment’s full response to solar activity.
Building on this success, China is launching the International Meridian Circle Program. Its goal is to establish all-weather, around-the-clock monitoring of the Sun-Earth space environment across all latitudes.
