On August 5, 2026 at precisely 11:35 pm (Pacific), the upper stage used by the Falcon 9 rocket that launched in 2025 the Blue Ghost and Hakuto-R lunar landers will impact the Moon.

Scientists have now published a paper [pdf], outlining the details of that impact and calling on the astronomical community, both professional and amateur, to conduct observations. The image to the right, showing the location on the Moon where the impact will occur, comes from Figure 1 of the paper. From the paper’s conclusion:

The upcoming Falcon 9 upper stage impact on the Moon on 2026 August 5, presents an ideal opportunity for observers in the Americas and space-based assets to study a significant lunar impact in real time. Potential observables from this event include the flash at the time of impact (likely lasting less than a second) and the ejecta plume (lasting minutes to tens of minutes) Although some specifics of the impact (such as its precise visual magnitude) remain unclear due to the complexity of the physical processes involved, this event is an ideal opportunity to calibrate measurements of flash brightness and plume dynamics against a known event, should either be detected.

This event also provides an opportunity to test pipelines for measuring flash properties to locate impact events seismically, and to better understand the multi-modal hazards posed to future lunar infrastructure and astronauts from space debris impacting the Moon. It also provides an opportunity to test our capability to monitor the cislunar environment. Given the renewed interest in the lunar exploration, the impact of artificial bodies on the Moon could is almost certain to become more frequent. To avoid uncontrolled increases in the amount of space debris in lunar orbit (as is the case now in low Earth orbit), advancing monitoring of cislunar space from ground- and space-based facilities will be key.

The scientists note that the impact will occur at night when the Moon is visible in South America and in the low and mid-latitudes of North America. Though the impact flash could be as bright as magnitude 3 (thus visible to the naked eye), its location during the lunar day will likely make it too faint for ordinary observers. They say that a telescope will be needed, that binoculars will not be sufficient.

The paper is also very enlightening in that it provides a detailed history of past observed lunar impacts, both natural and artificial.