On 2026-03-05, NASA reported that new observations from the James Webb Space Telescope collected on 2026-02-18 and 2026-02-26 refined the orbit of near-Earth asteroid 2024 YR4 enough to eliminate any chance of a lunar impact on 2032-12-22. NASA’s Center for Near-Earth Object Studies at JPL said the asteroid will pass the Moon at about 13,200 miles (21,200 km), and the previously cited lunar-impact probability dropped to zero.
For the Lunar Ark, the key technical implication is that better astrometry can collapse uncertainty fast enough to convert a nonzero hazard into a zero-risk outcome, which is exactly the decision boundary needed for protecting surface habitats, power systems, comms relays, and stored biospheres. The close pass also reinforces that the lunar environment remains operationally sensitive to small-body dynamics even when Earth is not threatened; a 21,200 km flyby is close enough to justify continuing impact-monitoring, ejecta-risk modeling, and redundancy planning for lunar assets.
Ark action: integrate this case into the Ark’s planetary-defense baseline as a worked example of rapid orbit refinement using JWST-class observations, and keep monitoring the Near-Earth Object pipeline, especially the NASA Center for Near-Earth Object Studies and ESA planetary-defense updates. Prioritize research on lunar impact consequences, secondary ejecta hazards, and sensor networks that can detect and characterize any future NEO with a potentially hazardous lunar trajectory before it becomes a systems problem.