Part of a SpaceX rocket used to launch a pair of robotic commercial lunar landers is expected to crash into the moon early Wednesday morning.
The Falcon 9 rocket lifted off on January 15, 2025, carrying the Blue Ghost lander developed by Texas-based Firefly Aerospace, as well as Tokyo-based Ispace’s Resilience lander. Blue Ghost successfully soft-landed on the moon in March 2025, while Resilience failed to land safely a few months later.
While the rocket’s first stage — the booster used for liftoff — returned to Earth, Falcon 9’s second, or upper, stage served as the in-space workhorse to propel the landers on their path to the moon.
For missions heading to low-Earth orbit, the nearby region where the International Space Station circles our planet, SpaceX and other operators usually dispose of the upper stage by allowing it to burn up Earth’s atmosphere, said Julianna Scheiman, director of NASA Science and Dragon Programs at SpaceX, at a Monday news conference.
“But for high energy missions, we need to perform a different maneuver to ensure the second stage itself is safe per the appropriate rules and regulations,” Scheiman said. “We did that here for the Ispace and Blue Ghost missions’ second stage, and what has happened is essentially a mixture of solar activity and gravity forces have put it on a path towards the moon.”
Independent astronomers used publicly available data to track the Falcon 9 upper stage and determine that it was on a collision course with the moon, according to NASA. The agency’s Center for Near Earth Object Studies, which tracks the orbits of space rocks that could crash into Earth, and very occasionally the moon, also confirmed the impact trajectory of the upper stage.
“There is no danger to Earth,” according to a statement shared by the agency with CNN. “NASA will continue to track the booster for training purposes, as well as later observe the impact site for scientific purposes.”
Astronomers across the Americas, who have the best chance of witnessing the impact expected to occur at 2:35 a.m. ET Wednesday, have aimed ground and space-based telescopes at the moon in hopes of witnessing the event. While there won’t be a way for the general public to watch the impact live, imagery will likely become available afterward.
Scientists can use this rare occurrence of an artificial object hitting the moon to learn more about Earth’s natural satellite — as well as prepare for how to shield astronauts and any future infrastructure sent there.
NASA is planning to create a more sustained human presence on the lunar surface through the Artemis program. But as more missions head for the moon, which does not have a protective atmosphere like Earth’s, managing the accumulation of space debris in lunar orbit will increasingly become an issue.
The rocket’s upper stage, estimated to be around 8,818 pounds (4,000 kilograms), is expected to hit the lunar surface near Einstein Crater, according to a preprint study authored by a group of scientists, including researchers at NASA.
The study, currently awaiting review, has been submitted for publication in The Astrophysical Journal Letters. The authors wanted to share their predictions for the impact ahead of time to enable astronomers to prepare for observing the event, said study coauthor Darryl Seligman, assistant professor in the department of physics and astronomy at Michigan State University.
But the impact won’t be visible with the naked eye and may be tough to spot through telescopes as well.
The impact flash, the moment when the rocket strikes the moon moving at an estimated 5,436 miles per hour (2.43 kilometers per second), will only last about a second at most.
“If you imagine the moon is a clock, it’ll sort of roughly hit where the 10 would be,” said Dr. Paul Wiegert, a professor of astronomy and physics at the Western University in London, Ontario, who was not involved with the study. “But that part of the moon is lit right now, so the bright flash will be muted by that brightness of the moon itself.”
However, the plume of debris generated by the long cylinder rocket may be illuminated by sunlight, allowing researchers to see it through telescopes, Wiegert added.
The Korean Pathfinder Lunar Orbiter will attempt to capture images of the upper stage prior to impact, and NASA’s Lunar Reconnaissance Orbiter will try to survey the impact site afterward. Scientists estimate the collision will create a crater with a diameter of 65 to 90 feet (20 to 30 meters), according to the study.
Space rocks regularly crash into the moon, and Apollo mission astronauts, as well as the Artemis II crew, reported glimpsing impact flashes as meteoroids slammed into the lunar surface. But impacts from artificial objects like the Falcon 9 upper stage have only occurred a handful of times, according to the study.
The event comes as SpaceX is under scrutiny around the release of its first-ever quarterly earnings report as a public company. The company’s shares have been on a rocky path since its blockbuster IPO in June.
Understanding lunar risks
An increase in lunar exploration means that more space debris may be likely to hit the moon in the future. Any space debris that poses a risk to Earth typically burns up in the atmosphere. But the moon has no air to protect its surface, Wiegert noted.
There is also no formalized tracking of debris that exists beyond our planet. Rather, surveys searching for potentially hazardous asteroids identify pieces of space junk that can then be tracked.
Since it’s difficult to track and spot objects that slam into the moon, a known event like the upper stage collision helps scientists gain insights into properties of the lunar surface, Wiegert said.
“What happens when an object crashes into the moon? We know it makes a crater, and of course it does eject material, but we don’t really understand that process in great detail,” Wiegert said. “And now that we have more spacecraft, and soon to have astronauts on the moon, we really want to understand that process better.”
Current estimates suggest that the rocket stage might launch rocky material as far as 500 miles (805 kilometers) from the site of impact before landing back on the lunar surface, Wiegert said. If an event like this were to occur while astronauts and any habitats, hardware or spacecraft were within the landing zone on the lunar surface, it would pose a significant threat.
“The objects are small rocks traveling at very high speeds, sort of comparable to bullets, so we want to understand these processes so that we can eliminate that as a source of risk,” he said.
To that end, researchers are exploring ways to potentially lower the odds of such collisions.
“As a scientist, I also am very excited to see the observation,” Scheiman said. “But it’s one of the things that we’re working in partnership with NASA and the other appropriate agencies: What is the best future disposal path for high energy missions that are in the sun-Earth-moon system?”
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