The Final Security Frontier: Using Privacy-Preserving Computation to Secure Satellite Rendezvous and Proximity Operations

Space is emerging as a critical domain for secure and privacy-preserving computing, driven by the rapid growth of commercial satellites and the increasing complexity of in-space operations. This need is particularly evident in satellite rendezvous and proximity operations (RPO), where multiple satellites must compute with private, identifying, or even classified information in order to operate safely at close distances. Secure multiparty computation (MPC) offers a promising foundation for privacy-preserving collaboration, but its suitability for in-space applications remains largely unexplored. This work provides a domain-informed analysis of satellite RPO and private computation techniques for two fundamental scenarios: collision avoidance and multi-point inspection. We design and evaluate a secure two-party computation for collision avoidance and a three-party computation for multi-point inspection using the MP-SDPZ compiler. Testing on radiation-tolerant NVIDIA Jetson hardware, we find that collision avoidance can be performed securely in 7.38 seconds in a semi-honest dishonest majority model, while multi-point inspection can be performed securely in 0.28 seconds in the semi-honest model and in 2.7 seconds in the malicious model. These findings demonstrate that MPC is both feasible and practical for privacy-preserving RPO under realistic hardware and threat assumptions. To our knowledge, this is the first work to provide granular assessment and experimentally validated MPC for in-space cooperative operations, opening a new direction for cybersecurity research in emerging space systems.