A SpaceX rocket booster is on track to hit the moon at several times the speed of sound

While there is no immediate danger, this crash highlights that space junk is increasingly expanding out of lower-Earth orbit

By Adam Kovac edited by Claire Cameron

A stray piece of a SpaceX Falcon 9 rocket is on course to smash into the moon’s surface at several times the speed of sound in August. The collision is likely to leave a crater—and it highlights the risk of space junk to the lunar surface at a moment when NASA and other national space agencies are pushing hard to return humans to the moon.

The wayward booster was spotted by independent astronomer Bill Gray, who develops and sells software dedicated to tracking celestial objects both artificial and natural. The rocket originally launched in January 2025 and carried other private space companies’ lunar landers: Firefly Aerospace’s Blue Ghost and Japanese firm ispace’s Hakuto-R. After the rocket set the landers on a path for the lunar surface, the booster was supposed to burn up following its reentry in Earth’s atmosphere. But that’s not what happened.

Instead it entered a 26-day-long orbit that took it up to 310,000 miles away from the planet. Its orbit intersects with that of the moon, according to Gray, but the two haven’t been in the same place at the same time. Per his calculations, that is set to change on August 5, at 2:44 A.M. EDT. At around that time, as the booster travels at roughly 5,400 miles per hour, it’s going to slam into the moon’s surface.

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Gray first noticed the collision course last September, but he says that while calculating the effects of gravity from Earth, the sun and the moon was straightforward, there was another variable that made things more complicated. The rocket booster was being hit by solar radiation pressure, which is caused by the photons blasted out of the sun. As those photons hit an object, they apply force. The amount is tiny, but it builds up over time.

“It’s the reason why, even now that we’re much closer to the event, I can be certain it’s going to hit, but there’s still an uncertainty of at least a few dozen kilometers as to where it’s going to hit,” says Gray, adding that his predicted timing of when the strike will occur could also be off by a few minutes. Most likely, the spot where it hits will be near the Einstein Crater on the moon’s western limb—that will make it difficult to see the impact from Earth.

It’s not the first time that Gray has predicted that a human-made object would smash into the moon. In 2022 he forecast that a Chinese rocket component from another lunar mission would also impact the moon—the ensuing crash created not just one crater but two. Altogether, such collisions highlight the risk of space debris to future lunar missions. Given the sheer vastness of space, it may seem unlikely that an object as small as a rocket booster could end up perfectly aligned for this kind of crash, but Gray argues otherwise.

“Eventually, your luck runs out, and you’re both in the same place at the same time,” he says.

As an isolated incident, the crash poses no imminent danger, Gray stresses. It’s a sign, however, that the space junk problem that has been plaguing lower-Earth orbit is already being exported to the moon. With both the U.S.’s and China’s space agencies planning to put humans on the moon in the next few years, that could eventually lead to real danger, warns John Crassidis, a professor at the University at Buffalo, who works with NASA and the U.S. Space Force on space junk solutions.

While the possibility of astronauts being struck by falling garbage is remote in the near term, Crassidis worries that in the coming decades, as more human-made objects are put into orbit around the moon, “we’re going to start to create a debris field,” he says. “We can definitely be a lot more careful about it.”

“From a philosophical point of view, don’t bring more problems that we have on Earth to the moon and then eventually Mars and other bodies like that,” he says, “because it’s going to cause issues someday.”

SpaceX did not immediately respond to a request for comment.