Spent SpaceX Falcon 9 Upper Stage Projected to Strike Moon
A discarded rocket stage from a January 2025 launch will impact the lunar surface, offering scientists a rare look at high-speed cratering.
A spent upper stage of a SpaceX Falcon 9 rocket is projected to impact the moon on August 5, 2026. The collision, expected between 06:34 and 06:44 UTC, will occur near the Einstein crater, turning a piece of orbital debris into an unplanned scientific experiment.
The hardware has been adrift since its launch on January 15, 2025, when it delivered Firefly Aerospace's Blue Ghost Mission 1 and ispace's Resilience landers. The stage will strike the lunar surface at approximately 5,400 mph—roughly seven times the speed of sound. The kinetic energy of the impact is estimated to be equivalent to three tons of TNT.
The Path to Impact
The upper stage was left in an unstable elliptical orbit following the delivery of its lunar payloads in early 2025. Julianna Scheiman of SpaceX noted that a maneuver intended to ensure the stage remained safe failed to lock it into a stable location. Subsequent gravitational forces and solar activity eventually pushed the hardware toward the moon. This event is not unprecedented; it follows previous accidental lunar impacts, including a NASA satellite in 2009 and a Chinese rocket segment in 2022.
Scientific Implications
While the impact poses no danger to Earth, it provides a unique opportunity for researchers to conduct "ejecta-plume science." By observing the collision, scientists can calibrate models of how debris behaves during high-speed impacts, which is critical for improving the safety of future crewed and robotic lunar missions. Brent Garry, a NASA LRO project scientist, indicated that targeting could be conducted about a week after the impact to inspect the site.
The Challenge of Space Junk
Beyond the immediate scientific gain, the event underscores the growing difficulty of managing space debris as lunar traffic increases. Bill Gray, a space expert with Project Pluto, stated that while the event is harmless, it highlights a "certain carelessness" regarding the disposal of leftover space hardware.
In response to these challenges, SpaceX has reportedly begun adopting different disposal trajectories for more recent missions, such as directing spent stages into heliocentric orbits to avoid similar accidental collisions in the future. Observers will now watch to see if the resulting impact site provides the data necessary to refine these orbital disposal standards.