A SpaceX Rocket Part Is Expected to Smack Into the Moon in August, Highlighting the Growing Problem of Space Junk
The unintended event also creates an opportunity for scientists and skywatchers to witness lunar impact dynamics in real time, although the debris will hit a sunlit portion of the moon from the perspective of Earth, making it hard to see
The upper stage of a SpaceX Falcon 9 rocket is estimated to hit the moon on August 5.
Gregory H. Revera via Wikimedia Commons under CC BY-SA 3.0
Something is about to smack into the moon—and no, it’s not asteroid 2024 YR4. It’s a part of a SpaceX rocket. And while the impact won’t directly cause harm to humans, the unintended event highlights the increasing amount of space debris cluttering Earth’s orbit.
The lunar impact was revealed by Bill Gray, the independent astrodynamicist and software developer behind Project Pluto, which supplies computer programs to astronomers. Last fall, his software for tracking orbits predicted that SpaceX’s junk would hit the moon on August 5, 2026, according to a statement. With more recent data, he estimates that the impact will happen around 2:35 a.m. U.S. Eastern Time.
“This may be of some (probably minor) scientific interest, and we may learn some things from it. It doesn’t present any danger to anyone, though it does highlight a certain carelessness about how leftover space hardware (space junk) is disposed of,” Gray writes in the statement.
Did you know? “Space balls” in Australia
In early July, large metallic-looking spheres started washing ashore on an Australian beach. Authorities determined that they were empty fuel vessels from a rocket, which are often called “space balls.”
Though debris close to Earth is tracked by some governmental agencies, space junk near the moon is tougher to trace, Marco Langbroek, a satellite tracking expert at Delft University of Technology in the Netherlands, tells Sky \& Telescope’s David Dickinson. “There currently is no dedicated tracking network for these objects: All tracking data comes from chance detections by near-Earth asteroid surveys.” And even those surprise detections can be lost.
It’s not the first time Gray has flagged space debris about to throw hands with Earth’s natural satellite. He previously predicted that a rocket booster would strike the moon in March 2022. He thought it would be a SpaceX part, but it turned out to be a booster from China’s Chang’e 5 T1 lunar mission, per Sky \& Telescope. The resulting impact crater was imaged by NASA’s Lunar Reconnaissance Orbiter.
The object headed for our celestial companion this time is a SpaceX Falcon 9 rocket’s upper stage, according to Gray. Stages are stacked parts of a rocket that have fuel and propel the vehicle. When one runs out of fuel post-launch, it detaches from the spacecraft and the next stage takes over. Falcon 9 has two stages, and the one currently hurtling toward the moon is the smaller of them. As Gray points out, however, it’s not small by most people’s standards—it’s around the height of a five-story building. The part was used on January 15, 2025, when lunar landers from Texas-based company Firefly Aerospace and Tokyo-based company ispace headed to the moon.
So what happens when the upper stage hits the moon? Probably nothing extraordinary, but scientists will be watching. The event will offer the chance to study lunar impact plume and dust dynamics, among other scientific interests, in real time, according to a non-peer-reviewed study posted to the preprint server arXiv on July 16. The study co-authors, which include Gray, encourage both professional and amateur astronomers to try observing it.
The rocket part will ram into our neighbor at an estimated nearly 5,500 miles per hour, and some of the energy from the impact will briefly create a flash of light. However, it’ll probably be tough to see, especially because it’ll hit an area being illuminated by the sun from Earthlings’ point of view.
“We expect the magnitude of this flash to be very, very faint,” study co-author William Cooke, meteoroid environment program manager at NASA, said in an information session by the agency’s Solar System Exploration Research Virtual Institute on June 12. Seeing “a flash that faint against the sunlit portion of the moon will be incredibly challenging.”
Nevertheless, ground- and space-based telescopes might be able to watch it and an accompanying plume of ejected material, the researchers write in the paper.
The rocket stage’s trajectory calls attention, once again, to the increasing amounts of space debris filling Earth’s orbit—and occasionally making it back to Earth.
“Infrastructure on the moon is currently sparse enough that we aren’t too worried about these kinds of uncontrolled impacts, but that will change in the future,” Anncy Thresher, a philosopher of science and applied ethicist at Northeastern University, says in a statement from the university. “We need to be proactive now about how to regulate and remove space junk to avoid catastrophes going forward.”