SpaceX Falcon 9 upper stage set to impact Moon near crater Einstein

On Aug. 5 at roughly 02:34 a.m. ET, the upper stage of a Falcon 9 rocket that delivered two lunar landers will collide with the Moon near the western-limb crater Einstein, traveling at about 5,400 mph, according to Bill Gray of Project Pluto, who first identified the trajectory.

The impact is expected to vaporize the booster, produce a brief flash of light and eject a plume of lunar dust and regolith, creating a new crater, said Benjamin Fernando, a postdoctoral researcher at Los Alamos National Laboratory and lead author of a preprint study on the event.

Fernando noted that because the mass and speed of the incoming stage are known, the impact can serve as a calibration event for techniques used to study natural meteoroid strikes, which are typically unpredictable. He added that measuring the composition of the resulting plume could provide insight into the local lunar material.

The researchers also see the collision as a chance to assess potential hazards for future crewed missions and lunar infrastructure, citing risks such as direct debris impact, flash-induced blindness, and indirect effects from ejecta clouds on spacecraft operations.

The upper stage was left in a high-Earth orbit after launching Firefly Aerospace’s Blue Ghost 1 lander and ispace’s Resilience lander on Jan. 15, 2025; Blue Ghost landed successfully in March, while Resilience was lost shortly before touchdown.

Fernando said SpaceX’s awareness of the eventual impact is unclear. He encouraged amateur astronomers with suitable telescopes to observe the event, though the flash is expected to be too faint for the naked eye and the likelihood of detection is low.