HELSINKI — A rocket stage expected to impact the moon is still most likely to belong to China’s 2014 moon mission, despite a denial from the country’s Ministry of Foreign Affairs.
The response from a Chinese foreign ministry spokesperson may have confused the mission in question, apparently referring to the 2020 “Chang’e-5 mission,” instead of the 2014 mission, Chang’e-5 T1.
The second stage of the Long March 5 rocket which launched the 2020 Chang’e-5 mission reentered the atmosphere over the Pacific Ocean a week after launch. The fate of the rocket upper stage from the 2014 mission is murkier.
Space tracking data from the U.S. Space Force’s 18th Space Control Squadron (18SPCS) suggests the upper stage (international designator 2014-065B) of the Long March 3C rocket which launched Chang’e-5 T1 reentered the atmosphere in 2015, apparently backing China’s denial.
However the reported orbital decay of the object may instead be an extrapolation of a single trajectory data point soon after launch, and therefore not reliable.
Bill Gray, the astronomer who first noted that a rocket stage was due to impact the moon back in January, believes this may be the case. If the reentry date is a prediction a year ahead of time then it that would be like trying to predict weather a year ahead of time, says Gray.
“It could be that 18SPCS did track it [2014-065B] over the following year. But if they had, they probably would have posted an updated trajectory publicly. They’re usually quite reliable about that,” Gray said in an updated post following Monday’s Foreign Ministry comment.
18SPCS did not respond to a request for comment by press time. Neither the China National Space Administration (CNSA) nor the State Administration for Science, Technology and Industry for National Defense (SASTIND) responded to emails from SpaceNews requesting clarification.
U.S. Space Force tracking is focused on lower orbits, relying mainly on radar for tracking data. Asteroid observers, using optical telescopes, are however understood to have tracked the object several times since, allowing Gray to state that the object would hit the moon in March.
The European Space Agency’s European Space Operations Centre (ESOC), which also has its own tracking capabilities and space object database, does not list the 2,800-kilogram rocket stage 2014-065B as having reentered the atmosphere. Once again however, ESA tracking focuses on low, medium and geosynchronous orbits.
CNSA established its Space Debris Monitoring and Application Center in 2015, at the National Astronomical Observatory of the Chinese Academy of Sciences, but does not keep a public space object database.
Gray, who runs the Project Pluto webpages and related software, is one of few who track deep space debris.
Independent spectral analysis by students at the University of Arizona also adds to the evidence that the object’s identity most likely belongs to China’s Chang’e-5 T1 mission.
“We took a spectrum and compared it with Chinese and SpaceX rockets of similar types, and it matches the Chinese rocket,” said associate professor Vishnu Reddy, who co-leads the University of Arizona’s Space Domain Awareness lab. “This is the best match, and we have the best possible evidence at this point.”
The interest in the object began in January when Bill Gray reported that a space object previously discovered by the Catalina Sky Survey and given the temporary name WE0913A was not a rock but likely a rocket stage and would impact the moon on March 4.
It was initially thought to be a second stage from the February 2015 SpaceX Falcon 9 launch of the DSCOVR climate observatory, but then found to be more likely a fit with 2014-065B from China’s Chang’e-5 T1 mission.
This led to the denial from China. “According to China’s monitoring, the upper stage of the rocket related to the Chang’e-5 mission entered into Earth’s atmosphere and completely burned up,” Foreign Ministry spokesperson Wang Wenbin said Feb. 21, in response to a question from the Associated Press, which specified the “lunar mission launched from China in 2014.”
The Chang’e-5 mission, apparently referenced by Wang, launched in November 2020, collecting 1.7 kilograms of fresh lunar samples from the moon and delivering them to Earth in December 2020.
Chang’e-5 T1 was a 2014 trial mission for the more ambitious Chang’e-5 lunar sample-return mission. It successfully tested a high-velocity spacecraft “skip reentry” after returning from the moon, verifying a reentry capsule could safely deliver lunar rocks to Earth.
The rocket upper stage which inserted Chang’e-5 T1 into lunar transfer orbit has apparently been in a chaotic orbit, transferring between the Earth and moon, ever since.
The Long March 3C rocket upper stage also carried the Manfred Memorial Moon Mission (4M) for Luxembourg. The 14-kilogram payload was designed to transmit signals during its journey to the moon. It is thought to be no longer active.
The issue is expected to become more important in coming years as both the United States and a number of partners and China and Russia are planning respective Artemis and International Lunar Research Station (ILRS) programs to establish a long term presence on the moon.
“The upcoming lunar impact illustrates well the need for a comprehensive regulatory regime in space, not only for the economically crucial orbits around Earth but also applying to the Moon,” Holger Krag, Head of ESA’s Space Safety Programme, said in a recent ESA release.