China executed a surprise orbital launch on Monday, successfully deploying the Shiyan-31 remote sensing test satellite into orbit without any prior warning. A Long March 2D rocket took flight at 6:00 a.m. Eastern (1000 UTC) on October 13 from the Jiuquan Satellite Launch Center, situated in the Gobi Desert of northwest China.
The China Aerospace Science and Technology Corporation (CASC) confirmed the successful launch approximately one hour after liftoff, identifying the payload as the Shiyan-31 satellite. According to CASC, the satellite is designed primarily to test new optical imaging technology, but further details were not disclosed, in line with the typical practice for missions in the Shiyan series. This announcement also served as the initial indication that the mission was underway.
The launch caught many observers off guard, as China typically issues temporary airspace closure notices (NOTAMs) several days before rocket launches. These notices specify falling-debris zones for stages and boosters, as well as the approximate launch window and trajectory. The absence of such notices for this mission suggests an unusually discreet operation.
The Shiyan-31 satellite was developed by CASC’s Shanghai Academy of Spaceflight Technology (SAST). The Long March 2D launch utilized a wider 4.0-meter-diameter fairing and can deliver 1,300 kilograms of payload to a 700-kilometer sun-synchronous orbit. SAST's statement included mission patches, one featuring an armillary sphere and five stars. Another patch shows an astrolabe.
The launch of Shiyan-31 comes two weeks after the launch of the Shiyan-30 satellites, also on a Long March 2D rocket. "Shiyan missions are typically opaque," but analysts suggest these satellites are used to trial new systems.
"Satellites in the series appear to have been used for a range of purposes, including technology demonstrations, space environment monitoring, electronic intelligence, remote sensing, space situational awareness and space operations such as rendezvous and proximity maneuvers (RPO)."
Monday’s launch marked China’s 61st orbital launch attempt of 2025. The next potential launch activity is expected to be Long March 8A and Long March 12 rocket launches from Hainan commercial spaceport Thursday, Oct. 16. The Shenzhou-21 crewed mission to the Tiangong space station could launch later in October.