Risks of Debris Between the Earth and the Moon for Future Exploration

• Increased lunar mission activity has made the management of cislunar space debris a critical safety priority.
• Researchers from the Chinese Academy of Sciences (CAS) have modeled debris cloud dispersion in Distant Retrograde Orbits (DROs) to develop mitigation strategies.
• While cumulative fragment impact remains low, debris poses significant high-velocity collision risks, necessitating improved environmental stewardship in space.

Growing Lunar Traffic and Collision Risks

• Major initiatives, including NASA's Artemis program and the China-Russia International Lunar Research Station (ILRS), are driving infrastructure development between Earth and the Moon.
• The rise in lunar orbiters and landers from various nations—including India, South Korea, and Japan—increases the density of objects in transit.
• Analysts warn that collisions could trigger a cascade effect similar to the Kessler Effect observed in Low-Earth Orbit (LEO), threatening long-term lunar infrastructure.

Research Findings and Modeling

• The team utilized a Circular Restricted Three-Body Problem (CR3BP) to construct reference orbits and the NASA Standard Breakup Model to simulate fragmentation.
• A Bicircular Restricted Four-Body Problem (BCR4BP) model was used to track debris propagation over a 30-day window.
• Simulations show that debris entering a defined 200 km "protected region" peaks shortly after a breakup, with some fragments remaining in the area for weeks.
• Potential collisions were categorized primarily as high-velocity fly-by events rather than persistent co-orbital threats.

Implications for Mission Safety

• Future lunar missions must integrate comprehensive risk assessments to comply with emerging planetary protection standards.
• Policies are expected to evolve to prevent the littering of cislunar space with spent rocket stages and defunct mission hardware.
• Sustainable exploration requires extending existing LEO debris mitigation protocols to the Earth-Moon system to ensure the safety of both crewed and robotic missions.