The Philippine Space Agency (PhilSA) has recommended precautionary measures following the launch of the Long March 5B on Monday, 31 October, at 03:37 PM Philippine Time from the Wenchang Space Launch Center in Hainan Island. The rocket is carrying the Mengtian laboratory module for the Tiangong space station, a research facility being built by China in orbit. Prior to the launch, PhilSA issued an advisory to all relevant government agencies on the estimated drop zones, and proposed the issuance of appropriate warnings on air and marine access.

Based on the Notice to Airmen (NOTAM) issued by the Civil Aviation Administration of China (CAAC) to the Civil Aviation Authority of the Philippines (CAAP), drop zone 1 is approximately 72 kilometers from Bajo de Masinloc, while drop zone 2 is approximately 39 kilometers from Busuanga, Palawan. Anticipated to fall within these areas are the “expected unburned debris,” or parts of the rocket designed to be discarded as the rocket enters outer space. These components get separated from the rocket minutes after the launch and are designed to shed over bodies of water to minimize the hazard of falling in populated areas. The booster stages are expected to fall on drop zone 1, while the rocket fairing is expected to fall on drop zone 2.

Fig. 1. Estimated drop zones from the Long March 5B rocket launch

While debris from Long March 5B is unlikely to fall on land features or inhabited areas in the Philippine territory, falling debris still poses a considerable risk to ships, aircraft, fishing boats, and other vessels that will pass through the drop zones. Actual drop zones may also vary because of various factors such as the Earth’s rotation, weather, and climate conditions. There is also a possibility for the debris to float around the area and wash toward nearby coasts. Furthermore, the possibility of an uncontrolled re-entry to the atmosphere of the rocket’s upper stages returning from outer space cannot be ruled out at this time.

PhilSA reiterates its earlier public advisory to immediately inform local authorities if suspected debris is sighted. PhilSA also cautions against retrieving or coming in close contact with these materials that may contain remnants of toxic substances such as rocket fuel.