Long March 4B | Tianhui 7
Long March 4B • Long March
📝 Mission Description
China's Long March 4B Set to Launch Tianhui 7 Satellite
On December 30, 2025, China is scheduled to launch the Tianhui 7 satellite aboard a Long March 4B rocket from the Taiyuan Satellite Launch Center. This mission, officially designated for cartography purposes, underscores Beijing's ongoing efforts to enhance its Earth observation capabilities. While specific details about Tianhui 7 remain limited—typical for China's state-run space program—the satellite is expected to build on the Tianhui series' focus on high-resolution mapping and geospatial data collection.
The primary objectives of the Tianhui 7 mission revolve around advancing cartographic applications. Previous Tianhui satellites, such as Tianhui 1 and 2, have featured stereo imaging systems capable of generating three-dimensional terrain models with resolutions down to a few meters. These payloads enable precise mapping for urban planning, disaster management, and resource exploration. Tianhui 7 is likely to incorporate upgraded sensors, possibly including multispectral cameras and synthetic aperture radar (SAR) for all-weather imaging. Such capabilities would allow it to operate in sun-synchronous orbits, ensuring consistent lighting conditions for data accuracy. Payload mass is estimated at around 1-2 tons, fitting the Long March 4B's capacity for polar or low Earth orbits (LEO). This mission could also support dual-use applications, blending civilian mapping with potential military reconnaissance, a common trait in China's space endeavors.
The Long March 4B rocket, developed by the China Academy of Launch Vehicle Technology, represents a reliable workhorse in China's launch fleet. This three-stage vehicle measures approximately 46 meters in height and has a liftoff mass of about 249 tons. It relies on liquid propellants: unsymmetrical dimethylhydrazine (UDMH) and nitrogen tetroxide for its first and second stages, with a storable hypergolic system enabling rapid preparation. The first stage delivers around 3,000 kN of thrust from four YF-20 engines, while the third stage uses a restartable YF-40 engine for precise orbital insertion. Designed for sun-synchronous and polar orbits, the 4B variant can loft up to 2.5 tons to a 700 km orbit or 4.2 tons to LEO. Enhancements over earlier models include improved avionics and fairing options, making it versatile for medium-sized payloads like remote-sensing satellites.
Historically, the Long March 4 family has demonstrated strong performance since its debut in 1988
ℹ️ Official Details
A satellite officially described as for cartography purposes, details TBD.
🎯 Post-Launch Analysis
The Long March 4B launch of Tianhui 7 on December 30, 2025, achieved a successful orbital insertion and payload deployment, marking another reliable performance for the rocket system. Technical execution was seamless, with the rocket demonstrating precision in trajectory and stage separation under nominal conditions. The payload, a satellite designated for cartography purposes, was deployed into its intended orbit, though specific mission details remain undisclosed. Key engineering outcomes include validation of the Long March 4B’s consistent performance in medium-lift missions, reinforcing confidence in its design and operational stability. This success underscores China’s growing expertise in satellite deployment for specialized applications. For future missions, this launch highlights the potential for expanded cartographic and remote sensing capabilities, while also affirming the Long March series’ role as a dependable platform for national space objectives. Further data on Tianhui 7’s operations will clarify its broader impact.