The Stellar Death Clock: Inner Solar Position System for Compass Navigation near Real-Time Automation

Deep-space autonomous navigation for planetary engineering and logistics requires a local positioning architecture that reduces dependence on Earth-based telemetry. This paper proposes the Inner Solar Position System (ISPS), a conceptual heliocentric multilateration network for the inner Solar System based on a small set of fixed infrared beacons deployed at thermodynamically favourable locations. The framework combines beacon time-of-flight measurements with a linearised relativistic state estimation model, using a Moore–Penrose pseudoinverse solution to reconstruct the spacecraft state vector under ideal line-of-sight conditions.The proposed deployment uses five reference nodes distributed across Mercury, Venus, the Earth–Moon system, Deimos, and Ceres to provide geometric redundancy and continuous coverage. A theoretical link-budget analysis indicates that near-infrared cross-links can support the required signal-to-noise ratio for interplanetary positioning under nominal assumptions, while the network architecture is designed to remain robust to individual-node degradation inside a low-entropy framework. The paper also outlines a reproducible workflow for future validation using real ephemerides and synthetic observation filtering.ISPS is presented as a conceptual model rather than a validated operational system. Its main contribution is to define a physically motivated and computationally tractable baseline for autonomous heliolocalization in the inner Solar System, with potential applications to shepherding probes, returnable spacecraft, and other closed-loop deep-space systems.