China's reusable space plane, shrouded in secrecy, has added a new layer of intrigue to its operations. After a four-day journey on its third mission, the "Divine Dragon" (Shenlong) appears to have deployed six objects into Earth's orbit. Amateur satellite trackers around the globe have been monitoring these objects closely, detecting emissions from some.
The six enigmatic objects, designated A through F, have sparked speculation. According to satellite tracker Scott Tilley, object A emits signals similar to those released by objects deployed during previous Shenlong missions. He noted that the signal is modulated with limited data, suggesting it could be "wingman" equipment similar to past releases. However, he emphasizes that speculation about this emission originating from another nearby object lacks concrete evidence.
Meanwhile, objects D and E appear to emit "placeholder" signals lacking data content. Notably, unlike earlier missions, these emissions are intermittent and brief, requiring days of meticulous tracking and data capture from dish antennas.
Tilley and other trackers, confident about the signal source, base their conclusion on several factors: observing the objects on their expected trajectories, confirming the absence of other known objects during data collection, and the unique signal modulation, "only seen previously from Chinese space planes using 2280MHz," Tilley explains.
This Shenlong mission, despite launching into a similar orbit as its predecessors, exhibits distinctive radio behavior. Additionally, the emissions from D and E, while potentially missed in earlier missions due to their intermittent nature, are a new element. In the coming days, close encounters between A and D/E are expected, as D and E have elliptical orbits while A's is near-circular. Perigee, the closest point to Earth in an elliptical orbit, will be the setting for these approaches.
This isn't the first time China's space plane has deployed unknown objects. Similar releases occurred during the September 2020 and August 2022 missions. Speculation suggests these objects could be service modules, test units for orbital payload deployment, or even small monitoring satellites, as reported by SpaceNews in November 2022.
The United States also operates a reusable robotic space plane, the Boeing-built X-37B. Similar to Shenlong, its exact operations and capabilities remain largely unknown. Interestingly, the U.S. Space Force is poised to launch its X-37B on a SpaceX Falcon Heavy rocket on December 28th, after facing delays.
This near-simultaneous launch timing doesn't go unnoticed. General Chance Saltzman, U.S. Space Force Chief of Space Operations, remarked at a recent conference that the Shenlong and X-37B are "two of the most watched objects on orbit" and that the timing of their launches "is probably no coincidence."
Clearly, the veil of secrecy surrounding China's space plane and its enigmatic deployments adds another layer of intrigue to the growing space race. While the purpose of these objects remains unknown, their presence and emissions warrant close observation and investigation.