An upper stage of a SpaceX rocket, launched over a year ago to deploy lunar landers, is on an unavoidable collision course with the moon. The rocket segment is predicted to impact the lunar surface on Wednesday at roughly 5,400 mph (8,700 kph), creating a new crater and ejecting dust and debris.
Space tracking expert Bill Gray, who has been monitoring the object, anticipates the impact near Einstein Crater on the moon's western side. The event is expected to be best viewed from the eastern United States, Canada, and much of South America in the early morning hours. The energy released by the collision is estimated to be equivalent to three tons of TNT.
While this particular piece of space debris does not pose a significant concern to scientists, its trajectory highlights the increasing issue of orbital crowding and the potential for future collisions. "Things are getting crowded up there," Gray noted.
Experts stated that the unintentional lunar impact could have been avoided if the rocket's upper stage had been directed into a solar orbit. This incident marks the second known accidental crash of a defunct rocket onto the moon; a Chinese rocket segment created craters on the lunar far side in 2022.
Observing the aftermath is of interest to scientists. Benjamin Fernando of Los Alamos National Laboratory explained that the low lunar gravity and lack of atmosphere mean ejected material could remain visible for extended periods. "Part of the reason for our interest in this event is to figure out how much of a hazard debris impacts pose to future astronauts," he said.
Fernando estimates the impact will create a crater approximately 90 feet (27 meters) in diameter and 16 feet (5 meters) deep, which is too small to be seen from Earth but detectable by spacecraft.
NASA's Lunar Reconnaissance Orbiter and South Korea's Danuri lunar orbiter are expected to capture images of the impact site before and after the event. Danuri is scheduled to pass within a few kilometers of the impact zone shortly before the collision.
The rocket segment measures about 40 feet (12 meters) long and weighs approximately 10,000 pounds (4,500 kilograms). It was part of a mission on January 15, 2025, that carried two private lunar landers. One, Firefly Aerospace's Blue Ghost, successfully landed on the moon, while the other, from Japan's ispace, did not.
Scientists draw parallels between this event and natural impacts, noting that well-tracked human-made strikes offer opportunities for study. Historically, NASA intentionally impacted lunar modules and rocket sections during the Apollo era for seismic data and in 2009 with the LCROSS mission to search for ice near the lunar south pole.
With increased activity and planned lunar missions, including efforts by the United States and China to land astronauts and private companies like SpaceX and Blue Origin developing landers, there is a growing need for improved debris monitoring and space traffic management around the moon. Retired astrophysicist Jonathan McDowell commented, "This impact will not be a problem. But in a future where there are long-term bases on the moon, similar impacts would be an issue and we need not to leave rocket stages in chaotic orbits of this kind."