The Invisible Planet

Simulates a realistic multi-planet system using Newtonian N-body physics, with a hidden planet whose gravity subtly perturbs the visible planets. It generates synthetic transit timing variations (TTVs) and detects the resulting orbital anomalies in noisy observations. An inverse solver then searches for the unseen planet's mass, orbit, and period from its gravitational fingerprint alone. Finally, it compares the recovered planet with the true simulation, turning an invisible cause into a measurable discovery.