Approximating the Position of Space Probes with Minimal Code

Calculating positions of space probes like Voyager or Parker Solar Probe is far harder than planets, because gravity assists shatter any single Keplerian orbit model. The solution: store a compact table of Keplerian element segments, each covering a quiet inertial phase between encounters. This yields 10-microsecond position lookups, ~4.5KB of data, and sub-arcminute accuracy — good enough for most non-scientific tools.