Design and Analysis of Close-Range Observation Strategies for Asteroid Kinetic-Impact Response Processes

Using simulated ejecta distributions of a 35 m target asteroid as scenario inputs, two typical impact-response cases—cratering and fragmentation—are investigated. For the cratering scenario, the ejecta exhibit a clear cone-shaped distribution, and a hovering strategy outside the ejecta cone can satisfy the safety constraint while maintaining favorable observation geometry.

For the fragmentation scenario, the ejecta show a highly irregular spatial distribution, making direct geometric safe-zone definitions ineffective. To provide a quantitative basis for avoidance design, an ejecta momentum-flux model based on annular integration is established, and a combined “pre-impact maneuver + trajectory optimization” strategy is proposed. Monte Carlo simulations considering release-position error, release-velocity error, maneuver magnitude error, maneuver direction error, and timing error show that the optimized strategy maintains strong safety robustness.