A recent study has brought closure to the case of the mysterious moon crash. On March 4, 2022, a rocket collided with the moon’s far side, creating a double crater that measured approximately 95 feet (29 meters) in width. Astronomers had been tracking the rogue rocket for weeks and accurately predicted its impact location and time.
The main mystery surrounding the crash was the identity of the object, known as WE0913A. Initially, astronomers believed it could be the upper stage of SpaceX’s Falcon 9 rocket that launched the DSCOVR satellite in February 2015. However, further investigations led astronomers to identify it as the third and uppermost stage of China’s Long March 3C rocket, which was used for the uncrewed Chang’e 5-T1 mission around the moon in October 2014.
Researchers from the University of Arizona (UA) had previously supported this conclusion, and their latest study now confirms it. Using ground-based telescope observations, trajectory analysis, and spectroscopic analysis, the UA team, led by Tanner Campbell, a doctoral student in the UA’s Department of Aerospace and Mechanical Engineering, presented evidence that WE0913A is indeed the Long March 3C rocket body from the Chang’e 5-T1 mission.
The study highlights two lines of evidence that leave little doubt about the rocket’s origin: its movement patterns and composition. However, China has attempted to cast doubt on this conclusion, claiming that the Long March 3C upper stage burned up in Earth’s atmosphere after the Chang’e 5-T1 launch. U.S. Space Command, however, contradicted this assertion, stating that the object never reentered Earth’s atmosphere.
The study also provides additional insights into the distinctive crater resulting from the moon crash. Using the rocket’s light curve, which represents changes in brightness over time, the researchers compared it with thousands of simulated space objects. They discovered that the rocket was tumbling in a stable manner, indicating the presence of a dumbbell-like object with considerable mass at each end.
The upper stage’s two engines, weighing a combined 2,400 pounds (1,090 kilograms) without fuel on Earth, are believed to be one of the masses. The other mass, located at the opposite end, likely contributed to the double crater formation. This mass is much larger than the standard instrument deck carried by the Long March 3C’s third stage, estimated to weigh around 60 pounds (27 kg). The researchers speculate that it could be additional support structure or instrumentation, but admit that the exact nature of this mystery object may never be known.
