Clear Orbit Secure Future 2026

Representative results from the model are shown below to illustrate how modelled collision probabilities vary first by altitude (spatial variation) and then over time at the most debris-dense altitude (around 805 km). These cases were selected because they represent the two main dimensions of debris-risk growth captured by the orbital population model.Cluster altitude (km)Collision rate (CR)Probability of first collision by 2032 775 0.00184 8% 840 0.00136 6% 1,000 0.00743 29% Modelling phase Altitude (km) PC(HNT) PC(LNT) Interpretation 2025–2030 515 0.1% 0.04%Low-risk region, rapid re-entry zone 2025–2030 805 1.3% 0.047% High-risk “bad neighbourhood” 2035–2040 805 1.5% 0.55%Persistent accumulation; risk slightly higher B3 Modelled clusters and event probabilities These clusters were defined as long-lived derelict aggregations with elevated collision potential. Each is modelled as a high-risk debris source zone. Modelled clusters and event probabilities TABLE 6 Variations on modelled collision probabilities TABLE 7 Note: Values show annual probabilities for a 3 m2 satellite. The first two rows compare altitudes within the same phase, while the last row shows temporal evolution at the highest-risk altitude (805 km) Clear Orbit, Secure Future: A Call to Action on Space Debris 27