Spent SpaceX Falcon 9 Stage to Impact Moon on Aug. 5, Offering Rare Scientific Opportunity
A decommissioned Falcon 9 upper stage will strike the lunar surface near the Einstein and Bell craters on Aug. 5, and researchers plan to observe the resulting ejecta plume and assess its implications for future missions.
On Aug. 5 a spent SpaceX Falcon 9 upper stage, the leftover from the launch that carried Firefly’s Blue Ghost-1 lander and the Japanese Hakuto-R Mission 2, will impact the Moon near the Einstein and Bell craters on the western limb. The collision is expected to generate an ejecta plume that could rise 75 to 100 kilometres and be bright enough to be detected by sensitive telescopes, according to simulations conducted by William Jo, a graduate research assistant at the University of Texas, Austin, and his team.
"Our calculations suggest the plume should be several orders of magnitude brighter than the dark-sky background for the first few minutes after impact," Jo told Space.com. He added that the event offers a chance to validate ejecta-plume models, which are currently based largely on natural impactors such as asteroids.
Researchers at Los Alamos National Laboratory, led by Benjamin Fernando, noted that the flash and plume are "potentially observable" from both ground-based and space-based assets. The study highlights the opportunity to test impact-localization techniques, gather data for future seismic experiments, and evaluate debris hazards for upcoming lunar activities.
"The maximum ballistic range of resolved particles is found to be slightly under 1,000 km, which is far enough to be significant from the perspective of presenting a hazard to future astronauts or infrastructure across much of the lunar surface," the authors wrote.
NASA’s Lunar Reconnaissance Orbiter will fly over the projected impact site about a week before and after the event, allowing scientists to refine the location and capture post-impact observations.
"After the impact we might have a little bit more knowledge of where it is. We can do some additional targeting about a week after the impact and get some targeting over where the site is," said Brent Garry, a project scientist for LRO.
The scientific community hopes the observation will improve understanding of artificial impact dynamics and inform safety measures for future lunar operations.