Just over a month after its most recent launch, a Chinese Chang Zheng 2C rocket lifted off from the Jiuquan Satellite Launch Center in Inner Mongolia, successfully carrying three new Chinese satellites into polar orbits around Earth. Although very little public information has been released about the rocket’s payloads, it is believed to consist of two Integrated Experimental Satellite (known natively as Ronghe Shiyan Weixing – RSX) spacecraft as well as a communications test satellite. Flight plan After several delays, which pushed the launch back from early August, the Chang Zheng 2C and its Yuanzheng-1 upper stage were successfully rolled out to South Launch Site (SLS) 2 at Jiuquan and prepared for launch. At 11:15 UTC (07:15 EDT, 19:15 Beijing time) on Tuesday, August 24, the four YF-21C engines that power the Chang Zheng 2C’s first stage ignited, providing the rocket with over 2,900kN of thrust and sending it and its three payloads on a path to orbit. Following completion of its burn, the first stage gave way to the second, powered by one YF-22E main engine and four YF-23C vernier engines for attitude control. The third and final stage was a Yuanzheng-1 restartable upper stage, which was used to deliver the payloads into their final orbits. The Yuanzheng-1 is powered by one YF-50D engine, which provides the stage with 6.5kN of thrust and allows for multiple burns throughout a six and a half-hour period. The restartable nature of the Yuanzheng-1 means the stage can be used to insert payloads into different orbits on the same mission, which allows for rideshare-type flights with more than one payload customer, as was the case with today’s launch. This functionality is desirable for building satellite constellations, and the Yuanzheng-1 has been called upon to launch spacecraft for China’s BeiDou Satellite Navigation System. Payloads Ronghe Shiyan Weixing-01 and 02 (RSW-01/02), the first two of the three spacecraft launched aboard that mission, are two experimental communications satellites built by the China Aerospace and Technology Corporation (CAST), China’s state-owned aerospace company that serves as the prime contractor for the China National Space Agency (CNSA). Although little is known about the two RSW spacecraft, it is believed they are intended to carry out satellite internet coverage experiments to aid in the development of a Chinese global satellite internet constellation under development by the Chinese government. The currently unnamed internet constellation appears to take after SpaceX’s Starlink and OneWeb’s global broadband satellite internet platforms and will consist of hundreds to thousands of satellites. The two RSW spacecraft seem to be akin to SpaceX’s TinTin A and TinTin B spacecraft, which were launched aboard a Falcon 9 in 2018 to test technologies for the Starlink constellation, which at the time was undergoing early development. RSW-01 and RSW-02 were deployed into a polar orbit. Even less information has been released regarding the third and final spacecraft on the mission. The third passenger is believed to be another experimental communications spacecraft built by the Aerospace Dongfanghong Satellite Company Limited (DFH), a subsidiary of CAST. As of publication, no further information has been released regarding the third payload. Lead image credit: Wang Jiangbo/Xinhua