Yaogan-40

History

Yaogan-40 is a Chinese military satellite series developed under the leadership of the China Academy of Space Technology. The spacecraft are officially described as being used mainly for electromagnetic environment detection and related technology experiments.

Yaogan-40 spacecraft have been deployed in groups of three using Long March 6A launch vehicles from the Taiyuan Satellite Launch Center. The first group entered orbit in September 2023, followed by additional groups in 2025 and 2026.

The satellites operate in near-polar low Earth orbits at altitudes of approximately 800 km. Four groups comprising twelve spacecraft had been launched by September 2026, forming a distributed orbital system for repeated global coverage.

Development and deployments

The first three Yaogan-40 satellites were launched on 10 September 2023 aboard a Long March 6A. This initial deployment established the basic three-spacecraft group configuration used by subsequent launches.

A second Yaogan-40 group was launched in May 2025, followed by a third group in September 2025. Each deployment added three spacecraft to similar near-polar orbital regimes.

The fourth group, designated Yaogan-40 Group-04, was launched on 24 September 2026 at 08:46 UTC. A Long March 6A lifted off from Launch Complex 9A at the Taiyuan Satellite Launch Center and deployed three additional spacecraft. This increased the number of launched Yaogan-40 satellites to twelve.

Design

Detailed information about the Yaogan-40 spacecraft bus, dimensions, mass, power system, sensors, communications equipment, and propulsion has not been publicly confirmed in the available material. The satellites were developed under the leadership of the China Academy of Space Technology.

Mission

The stated mission of Yaogan-40 is electromagnetic environment detection and related technology experimentation. The series is associated with China's military satellite program, while the exact operational payloads and collection methods remain undisclosed. The mission description is consistent with a possible signals-intelligence role, but this specific function has not been officially confirmed.

Orbital architecture

Yaogan-40 satellites operate in near-polar low Earth orbit at approximately 800 km altitude. The spacecraft are launched in groups of three, allowing multiple satellites to operate within each deployment group.

The first four groups occupy orbital planes separated by about 72 degrees in right ascension of the ascending node. This arrangement is consistent with a potential five-plane architecture if another group is added, although completion of such a constellation has not been confirmed.

Operational history

By September 2026, four Yaogan-40 groups had reached orbit, representing twelve launched spacecraft. Their near-polar trajectories allow coverage across most of the Earth's surface as the planet rotates beneath their orbital paths.

The fourth group joined the nine Yaogan-40 satellites launched during 2023 and 2025. Its deployment expanded the orbital network available for electromagnetic environment detection and associated technology experiments.

Specifications (Yaogan-40 Group-04 satellites)

General characteristics

• Type: Military satellite for electromagnetic environment detection and technology experiments
• Developer: Developed under the leadership of the China Academy of Space Technology
• Group size: Three satellites
• Launch date: 24 September 2026
• Launch time: 08:46 UTC
• Launch vehicle: Long March 6A
• Launch site: Taiyuan Satellite Launch Center, Launch Complex 9A

Orbit

• Orbit class: Low Earth orbit
• Orbit geometry: Near-polar
• Altitude: Approximately 800 km