Spent Falcon 9 upper stage forecast to impact the Moon on Aug. 5, 2026

Collision Next Week: Spent SpaceX Rocket Set To Slam Into Moon A spent SpaceX Falcon 9 upper stage is forecast to slam into the moon near Einstein Crater early Wednesday morning, potentially producing the first impact plume observed from Earth against the lunar surface's sunlit side. William Jo, a doctoral candidate at the University of Texas at Austin's Cockrell School of Engineering, and five co-authors posted a preprint to arXiv detailing the expected lunar impact of the spent upper stage rocket. Using a high-resolution physics simulation, the researchers modeled what could happen when roughly 3,900 kilograms of hollow rocket hardware slams into the lunar surface: On Aug. 5 at 06:34 UTC, a Falcon 9 upper stage (~3,900 kg) will strike the lunar surface at 2.43 km/s, yielding a potentially visible debris plume. We present a study of the expected impact dynamics and resulting possibly observable debris field. The debris plume should reach roughly 15 to 20 km in altitude for the ejecta curtain and 75 to 100 km for the central ejecta spike, extend 183 km laterally from the impact point near the sunlit limb, and yield a peak dust column density above 10 km altitude of 6.08*10^7 m^-2. Simulated I/F exceeds dark-sky background brightness by several orders of magnitude for the first few minutes after impact, reaching I/F = 1.27*10^-3 at the earliest resolved time (t = 5 s). Above 10 km, peak I/F reaches 1.33*10^-5, still several orders of magnitude brighter than the dark sky. NEWS 🚨: A Falcon 9 upper stage abandoned in orbit since Jan. 2025 will hit the Moon on August 5 at ~5,437 mph (8,750 km/h) It's projected to carve out a 100-foot crater pic.twitter.com/20hOVAhsVv — Latest in space (@latestinspace) July 29, 2026 Jo and the other researchers hope the unplanned collision next week will provide insight into lunar geology and the risks posed by discarded rockets as the US, China, and private companies plan future moon bases. Tyler Durden Sat, 08/01/2026 - 21:35

"Space.com and The Guardian are reporting that the Falcon 9 upper stage leftover from the launch of the Firefly Blue Ghost-1 lander on Jan. 15, 2025 is due to impact the Moon on Aug. 5, 2026," writes longtime Slashdot reader fahrbot-bot. From a report: Onboard the same flight was the Hakuto-R Mission 2, called Resilience, a robotic lunar lander developed by the Japanese company ispace. According to a new study by an international team, the resulting impact plume may briefly be bright enough to see against the dark sky near the moon's edge. That means it might be visible to moongazers with sufficiently sensitive telescopes. This head-on collision of the errant stage is expected to occur near the Einstein and Bell craters near the western lunar limb. It may well be visible to ground and space-based assets. Using special physics simulations to model the impact, William Jo, a graduate research assistant at the University of Texas, Austin and colleagues predict the debris plume from the impact will have the central ejecta spike reaching roughly 47 miles to over 60 miles (75 kilometers to 100 kilometers) altitude. "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. "So the plume should be visible, though I'd stress this is a single nominal case. The real one will look different, and the numbers are on the optimistic side. But the point worth making is that the flash isn't really the story here." Jo emphasized that there's great slam-dunk science to be had. "Watching this one gives us a rare chance to open up ejecta-plume science and calibrate those models against a real event, which matters for every future thing we deliver to the moon," Jo said. Read more of this story at Slashdot.