An empty upper stage from a SpaceX Falcon 9 rocket struck the moon on Wednesday, traveling at 8,700 kilometers per hour.
The Impact: Trajectory, Timing, and Expected Crater Size
The abandoned rocket component crashed onto the lunar surface on Wednesday morning, according to observations and trajectory tracking. The object was the upper stage of a Falcon 9 rocket originally launched on January 15, 2025, from Florida, which brought two commercial lunar landers on their way to the moon. After letting those go, the stage was left behind in space. Normally such rocket stages burn up in the atmosphere or end up in the ocean, but this stage remained without fuel, floating in an elongated orbit that could no longer be controlled. Solar activity and gravity eventually changed its path so that the object crashed into the moon, and according to SpaceX, the impact was unintended.
Measuring 14 meters in length and weighing 4,000 kilograms, the segment is roughly the length of a London bus and flew toward the moon at about 8,700 kilometers per hour, or seven times the speed of sound. The collision was predicted for 08:35 Dutch time, coming down near the Einstein crater on the difficult-to-observe western edge of the moon. NASA expected that a crater about 18 meters wide and 3.5 meters deep was formed by the impact, while scientists estimated it could measure up to 27 meters in diameter and 5 meters in depth on the lit western edge of the satellite, hurling tons of lunar dust and rock after a flash. The U.S. space agency NASA published a communiqué stating that the impact poses no danger to the Earth.
Satellite Observations and Historical Context
Because the moon is already very bright by nature and the collision produced a brief, fast flash of light lasting less than a second without being captured live, astronomers could not immediately confirm the impact on Wednesday. South Korea’s space agency KASA distributed the first images showing the impact of the rocket piece, while South Korea’s Danuri satellite and NASA’s uncrewed lunar reconnaissance orbiter will take photos of the impact site. Emmanuel Jehin, astrophysicist at the University of Liège, explained in an interview that the expected flash and plume of escaping matter were hard to see against the bright lunar background, and that analyzing the taken images can take a few hours or even days to truly distinguish if the impact was clearly visible. However, Jehin affirmed that they were completely certain it had indeed taken place.
This debris marks the second known out-of-service rocket to have accidentally crashed onto the moon, following a similar incident in 2022 involving a Chinese rocket stage. Meanwhile, according to NASA, a meteoroid with comparable energy impacts the moon about once every six days, and meteorite impacts happen daily.
Debate Over Space Debris and Corporate Accountability
The unplanned crash does not present any risk to the Earth according to specialists, but it raises the question of how to handle left-behind space debris, says space criminologist Yarin Eski. While scientists are not particularly worried about this specific piece of debris, space experts estimate that the collision could have been avoided if the upper stage had been placed on an orbit around the Sun. Even though SpaceX never intended to hit the moon, the event revives the debate on space debris and the growing threat they represent, while offering an opportunity to gather lunar data and refine tracking techniques for objects in space.
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