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Megaconstellation Collision Risk Assessment Scaling
The number of active satellites has increased from ~2,000 in 2019 to over 10,000 in 2025, driven primarily by megaconstellations (Starlink, OneWeb, Kuiper). The conjunction assessment system — which identifies potential collisions and triggers avoidance maneuvers — was designed for hundreds of tracked objects and generates thousands of false-alarm alerts per genuine risk. As constellation sizes grow toward 50,000+ planned satellites, the number of conjunction alerts scales quadratically with object count, and the current system cannot distinguish actionable threats from noise without human analysts who cannot keep pace.
A single collision in low Earth orbit generates thousands of debris fragments, each capable of destroying another satellite (the Kessler syndrome). The 2009 Iridium-Cosmos collision created over 2,000 trackable fragments still in orbit. With $300+ billion of space infrastructure at risk and the prospect of cascading collisions that could render entire orbital shells unusable for decades, the conjunction assessment problem is existential for the commercial space industry. Current operators report receiving hundreds to thousands of conjunction warnings per satellite per year, with false alarm rates exceeding 99.9%.
The U.S. Space Command's conjunction data messages (CDMs) provide basic screening, but positional uncertainties (especially for objects without GPS) produce enormous alert volumes. SpaceX's autonomous collision avoidance system on Starlink maneuvers satellites based on onboard assessment, but this creates coordination problems with other operators who cannot predict Starlink's maneuvers. ESA's collision avoidance system uses a multi-step screening process (from thousands of events to a handful of actionable cases), but each step requires updated tracking data that arrives asynchronously. Machine learning approaches to filter alerts have shown promise in retrospective analysis but struggle with the rarity of actual collision events (class imbalance) and the catastrophic cost of false negatives.
Better orbital tracking data (especially for sub-10-cm objects) would reduce positional uncertainty and shrink the false-alarm volume. Standardized inter-operator data sharing — so constellation operators can share planned maneuvers in near-real-time — would prevent the current problem of cascading avoidance maneuvers. A probabilistic framework that quantifies collision risk continuously (rather than per-conjunction) could shift from event-based alerting to risk-budget management. This is fundamentally a data fusion and decision-under-uncertainty problem.
A team could build a simulation of conjunction assessment scaling using publicly available TLE (two-line element) data from Space-Track.org, modeling how alert volume and false alarm rate scale with constellation size. Alternatively, a team could prototype a machine learning classifier for conjunction screening using historical CDM data (available through the Space Data Association), focusing on reducing false positives while maintaining zero false negatives. The algorithmic and data science aspects are accessible; the space domain knowledge can be acquired.
Related to `space-debris-small-object-tracking-gap` (which addresses the detection/tracking side) and `space-debris-non-cooperative-capture` (which addresses physical removal). This brief focuses on the decision-making and data processing layer between tracking and action. The multi-institution tag passes the three-criteria test: multiple operators (SpaceX, OneWeb, ESA, NASA, DoD) each control orbital slots and maneuver authority that others cannot substitute; inter-operator coordination is the binding constraint; this is structural, not solvable by a single entity. The worsening tag passes the three-requirement test: collision probability scales quadratically with object count (specific mechanism), tracked objects have increased 5× since 2019 (evidence of trajectory), and the alert-processing capacity gap is widening faster than mitigation (barrier worsening).
ESA Space Debris Office, "ESA's Annual Space Environment Report," 2024; Aerospace Corporation, "Large Constellation Disposal and Collision Avoidance Analysis," 2023; SpaceNews coverage of conjunction assessment scaling challenges, 2023–2024