China’s Shijian-31 Sweeps GEO Every 23 Days in Novel 12.5-Hour Molniya Orbit
Updated
Updated · SpaceNews · Jul 22
China’s Shijian-31 Sweeps GEO Every 23 Days in Novel 12.5-Hour Molniya Orbit
3 articles · Updated · SpaceNews · Jul 22
Summary
Shijian-31, launched June 16, is operating in an unusual Molniya-type orbit that lets it scan the full geostationary belt roughly once every 23 days, according to outside tracking analyses.
A 12.5-hour period and equatorial apogee near 39,900 km make the orbit atypical: instead of revisiting the same longitude, the satellite shifts about 15.7 degrees each pass and loiters above GEO for broad surveillance.
Integrity ISR and ComSpOC say the design gives China a rare top-down view of satellites in GEO, while a roughly 50 meters-per-second retrograde burn could lower apogee enough for direct passes through the GEO neighborhood.
CASC has described the classified satellite only as being for “space environment exploration,” but analysts say the mission fits a wider push toward inspector satellites and stronger space situational awareness in GEO.
Why did China put Shijian-31 in a never-before-seen orbit that can sweep the entire GEO belt in 23 days?
Could a small maneuver turn Shijian-31 from a watcher above GEO into a direct inspector of valuable geostationary satellites?
The Shijian-31 Satellite: China’s Passive Sweep Strategy and the Geopolitical Battle for Geostationary Orbit
Overview
China’s Shijian-31 satellite, launched in June 2026, uses a unique 12.5-hour orbit to passively sweep the entire geostationary belt every 23 days, allowing China to gather persistent intelligence on foreign satellites without provoking diplomatic incidents or burning extra fuel. Its high-altitude, stealthy profile makes it difficult for adversaries to track or analyze, while a small maneuver could quickly shift it into an active surveillance role. This approach contrasts with the more provocative tactics of US and Russian satellites, and has prompted calls for new international norms as commercial operators face growing risks from debris and military activity in crowded orbits.