China launched the Pathfinder mission for its Tanyuan space science program from Jiuquan at 7:41 p.m. Beijing time on November 11, 2026. A Long March 2D rocket carried the spacecraft into their intended orbit, according to the National Space Science Center.
The mission comprises four satellites, designated A, B, C, and D. It is designed for a two-year mission in a 600-kilometer dawn–dusk sun-synchronous orbit. The three spacecraft are intended to operate in formation as a distributed low-frequency interferometric imaging experiment.
Satellite A carries instruments for magnetic and velocity-field imaging, gamma-ray detection, atmospheric-boundary-layer laser measurements, plasma measurements, and space-weather monitoring. The National Space Science Center leads the overall project; the Chinese Academy of Sciences’ Innovation Academy for Microsatellites supplies the satellite system.
The launch report from Xinhua, published that evening, identified the flight as the 677th mission of the Long March rocket family. The launch site is one of the facilities covered in New Space Economy’s review of China’s launch sites.
Formation flying places separate spacecraft in a coordinated arrangement. For an interferometer, measurements from separated receivers are combined to study incoming radiation. The distances between receivers and the timing of their measurements become part of the observing system, so measuring the spacecraft’s relative positions is linked directly to the scientific instrument.
Pathfinder’s planned sequence includes separating satellite A from the B–C–D assembly, deploying the remaining spacecraft, and testing formation control and intersatellite measurements. Instrument testing follows deployment. After the technology-verification phase, the mission is intended to conduct space-environment monitoring demonstrations and research.
The National Space Science Center connects the tests with future missions including Hongmeng and Kuafu-2. Pathfinder provides an orbital setting for testing selected payload technologies before their use in those later scientific programs. Its immediate work is the deployment and operation of the four spacecraft and their instruments.
